Provided by: groff_1.22.3-10_amd64 bug


       refer - preprocess bibliographic references for groff


       refer [ -benvCPRS ] [ -an ] [ -cfields ] [ -fn ] [ -ifields ]
             [ -kfield ] [ -lm,n ] [ -pfilename ] [ -sfields ] [ -tn ]
             [ -Bfield.macro ] [ filename... ]


       This  file  documents  the  GNU  version of refer, which is part of the
       groff  document  formatting  system.   refer  copies  the  contents  of
       filename... to the standard output, except that lines between .[ and .]
       are interpreted as  citations,  and  lines  between  .R1  and  .R2  are
       interpreted as commands about how citations are to be processed.

       Each  citation  specifies  a  reference.   The  citation  can specify a
       reference that is contained in a bibliographic database by giving a set
       of  keywords  that  only that reference contains.  Alternatively it can
       specify a reference by supplying a database record in the citation.   A
       combination of these alternatives is also possible.

       For  each  citation,  refer  can produce a mark in the text.  This mark
       consists of some label which can be separated from the  text  and  from
       other labels in various ways.  For each reference it also outputs groff
       commands that can be used by a macro package  to  produce  a  formatted
       reference  for  each  citation.   The output of refer must therefore be
       processed using a suitable macro package.  The -ms and -me  macros  are
       both  suitable.   The  commands to format a citation's reference can be
       output immediately  after  the  citation,  or  the  references  may  be
       accumulated,  and  the  commands  output  at  some later point.  If the
       references  are  accumulated,  then  multiple  citations  of  the  same
       reference will produce a single formatted reference.

       The  interpretation  of  lines between .R1 and .R2 as commands is a new
       feature of GNU refer.  Documents making use of this feature  can  still
       be processed by Unix refer just by adding the lines

              .de R1
              .ig R2
       to  the  beginning  of  the  document.  This will cause troff to ignore
       everything between .R1 and .R2.  The effect of some commands  can  also
       be  achieved  by  options.   These  options  are  supported  mainly for
       compatibility with Unix refer.  It is usually more  convenient  to  use

       refer  generates  .lf  lines  so  that  filenames  and  line numbers in
       messages produced by commands that read refer output will  be  correct;
       it  also interprets lines beginning with .lf so that filenames and line
       numbers in the messages and .lf lines that it produces will be accurate
       even if the input has been preprocessed by a command such as soelim(1).


       It is possible to have whitespace between a command line option and its

       Most options are equivalent to commands (for  a  description  of  these
       commands see the Commands subsection):

       -b     no-label-in-text; no-label-in-reference

       -e     accumulate

       -n     no-default-database

       -C     compatible

       -P     move-punctuation

       -S     label "(A.n|Q) ', ' (D.y|D)"; bracket-label " (" ) "; "

       -an    reverse An

              capitalize fields

       -fn    label %n

              search-ignore fields

       -k     label L~%a

              label field~%a

       -l     label A.nD.y%a

       -lm    label A.n+mD.y%a

       -l,n   label A.nD.y-n%a

       -lm,n  label A.n+mD.y-n%a

              database filename

       -sspec sort spec

       -tn    search-truncate n

       These  options  are  equivalent  to  the  following  commands  with the
       addition that the filenames specified on the command line are processed
       as if they were arguments to the bibliography command instead of in the
       normal way:

       -B     annotate X AP; no-label-in-reference

              annotate field macro; no-label-in-reference

       The following options have no equivalent commands:

       -v     Print the version number.

       -R     Don't recognize lines beginning with .R1/.R2.


   Bibliographic databases
       The bibliographic  database  is  a  text  file  consisting  of  records
       separated  by one or more blank lines.  Within each record fields start
       with a % at the beginning of a line.  Each field has  a  one  character
       name  that immediately follows the %.  It is best to use only upper and
       lower case letters for the names of fields.   The  name  of  the  field
       should  be  followed  by exactly one space, and then by the contents of
       the field.  Empty fields are ignored.  The conventional meaning of each
       field is as follows:

       %A     The name of an author.  If the name contains a title such as Jr.
              at the end, it should be separated  from  the  last  name  by  a
              comma.   There can be multiple occurrences of the %A field.  The
              order is significant.  It is a good idea always to supply an  %A
              field or a %Q field.

       %B     For an article that is part of a book, the title of the book.

       %C     The place (city) of publication.

       %D     The  date of publication.  The year should be specified in full.
              If the month is specified, the name rather than  the  number  of
              the  month  should be used, but only the first three letters are
              required.  It is a good idea always to supply a %D field; if the
              date  is  unknown,  a  value  such as in press or unknown can be

       %E     For an article that is part of a book, the name of an editor  of
              the  book.  Where the work has editors and no authors, the names
              of the editors should be  given  as  %A  fields  and  , (ed)  or
              , (eds) should be appended to the last author.

       %G     US Government ordering number.

       %I     The publisher (issuer).

       %J     For an article in a journal, the name of the journal.

       %K     Keywords to be used for searching.

       %L     Label.

       %N     Journal issue number.

       %O     Other  information.   This  is usually printed at the end of the

       %P     Page number.  A range of pages can be specified as m-n.

       %Q     The name of the author, if the author is  not  a  person.   This
              will  only be used if there are no %A fields.  There can only be
              one %Q field.

       %R     Technical report number.

       %S     Series name.

       %T     Title.  For an article in a book or journal, this should be  the
              title of the article.

       %V     Volume number of the journal or book.

       %X     Annotation.

       For  all  fields except %A and %E, if there is more than one occurrence
       of a particular field in a record, only the last  such  field  will  be

       If  accent  strings  are  used,  they should follow the character to be
       accented.  This means that the AM macro  must  be  used  with  the  -ms
       macros.   Accent  strings  should  not be quoted: use one \ rather than

       The format of a citation is
              flags keywords

       The opening-text, closing-text and flags components are optional.  Only
       one of the keywords and fields components need be specified.

       The keywords component says to search the bibliographic databases for a
       reference that contains all the words in keywords.  It is an  error  if
       more than one reference if found.

       The  fields  components  specifies  additional  fields  to  replace  or
       supplement those specified in the reference.  When references are being
       accumulated  and  the  keywords component is non-empty, then additional
       fields should be specified only on the first occasion that a particular
       reference is cited, and will apply to all citations of that reference.

       The  opening-text  and  closing-text  component specifies strings to be
       used to bracket the label instead  of  the  strings  specified  in  the
       bracket-label command.  If either of these components is non-empty, the
       strings specified in the bracket-label command will not be  used;  this
       behaviour  can  be  altered using the [ and ] flags.  Note that leading
       and trailing spaces are significant for these components.

       The flags component is a list of non-alphanumeric  characters  each  of
       which  modifies  the treatment of this particular citation.  Unix refer
       will treat these flags as part of the keywords and so will ignore  them
       since  they  are  non-alphanumeric.   The following flags are currently

       #      This says to use the label specified by the short-label command,
              instead  of  that  specified  by the label command.  If no short
              label has  been  specified,  the  normal  label  will  be  used.
              Typically  the  short  label is used with author-date labels and
              consists of only the date and possibly a disambiguating  letter;
              the # is supposed to be suggestive of a numeric type of label.

       [      Precede  opening-text  with  the  first  string specified in the
              bracket-label command.

       ]      Follow closing-text with the  second  string  specified  in  the
              bracket-label command.

       One  advantages  of  using  the [ and ] flags rather than including the
       brackets in opening-text and closing-text is that you  can  change  the
       style  of  bracket  used  in the document just by changing the bracket-
       label command.  Another  advantage  is  that  sorting  and  merging  of
       citations will not necessarily be inhibited if the flags are used.

       If  a label is to be inserted into the text, it will be attached to the
       line preceding the .[ line.  If there is no such line,  then  an  extra
       line will be inserted before the .[ line and a warning will be given.

       There  is  no  special  notation  for  making  a  citation  to multiple
       references.  Just use a sequence of citations, one for each  reference.
       Don't  put  anything  between  the  citations.   The labels for all the
       citations will be attached to the line preceding  the  first  citation.
       The labels may also be sorted or merged.  See the description of the <>
       label expression, and of the sort-adjacent-labels and abbreviate-label-
       ranges  command.  A label will not be merged if its citation has a non-
       empty opening-text or closing-text.  However, the labels for a citation
       using the ] flag and without any closing-text immediately followed by a
       citation using the [ flag and without any opening-text  may  be  sorted
       and  merged even though the first citation's opening-text or the second
       citation's closing-text is non-empty.  (If you  wish  to  prevent  this
       just make the first citation's closing-text \&.)

       Commands  are  contained  between  lines  starting  with  .R1  and .R2.
       Recognition of these lines can be prevented by the -R option.   When  a
       .R1  line  is  recognized  any  accumulated references are flushed out.
       Neither .R1 nor .R2 lines, nor anything between them is output.

       Commands are separated by newlines or ;s.  # introduces a comment  that
       extends  to  the  end  of  the line (but does not conceal the newline).
       Each command is broken up into words.  Words are separated by spaces or
       tabs.   A  word  that  begins  with " extends to the next " that is not
       followed by another ".  If there is no such " the word extends  to  the
       end  of  the line.  Pairs of " in a word beginning with " collapse to a
       single ".  Neither # nor ; are recognized inside "s.   A  line  can  be
       continued by ending it with \; this works everywhere except after a #.

       Each  command  name  that  is  marked with * has an associated negative
       command no-name that undoes the effect of name.  For example,  the  no-
       sort  command  specifies  that  references  should  not be sorted.  The
       negative commands take no arguments.

       In the following description each argument must be a single word; field
       is  used for a single upper or lower case letter naming a field; fields
       is used for a sequence of such letters; m and n are  used  for  a  non-
       negative  numbers;  string is used for an arbitrary string; filename is
       used for the name of a file.

       abbreviate* fields string1 string2 string3 string4
                                Abbreviate the  first  names  of  fields.   An
                                initial  letter will be separated from another
                                initial letter by string1, from the last  name
                                by  string2, and from anything else (such as a
                                von or de) by string3.   These  default  to  a
                                period  followed  by a space.  In a hyphenated
                                first name, the initial of the first  part  of
                                the  name will be separated from the hyphen by
                                string4;  this  defaults  to  a  period.    No
                                attempt is made to handle any ambiguities that
                                might result  from  abbreviation.   Names  are
                                abbreviated  before  sorting  and before label

       abbreviate-label-ranges* string
                                Three or more adjacent labels  that  refer  to
                                consecutive  references will be abbreviated to
                                a  label  consisting  of  the   first   label,
                                followed by string followed by the last label.
                                This is mainly useful with numeric labels.  If
                                string is omitted it defaults to -.

       accumulate*              Accumulate  references  instead of writing out
                                each   reference   as   it   is   encountered.
                                Accumulated  references  will  be  written out
                                whenever a reference of the form


                                is encountered, after  all  input  files  have
                                been  processed,  and  whenever  .R1  line  is

       annotate* field string   field is an annotation; print it at the end of
                                the  reference  as a paragraph preceded by the


                                If string is omitted it will default to AP; if
                                field  is  also  omitted it will default to X.
                                Only one field can be an annotation.

       articles string...       string... are definite or indefinite articles,
                                and  should  be  ignored at the beginning of T
                                fields when sorting.  Initially, the, a and an
                                are recognized as articles.

       bibliography filename... Write  out all the references contained in the
                                bibliographic  databases   filename...    This
                                command should come last in a .R1/.R2 block.

       bracket-label string1 string2 string3
                                In  the  text, bracket each label with string1
                                and  string2.   An   occurrence   of   string2
                                immediately followed by string1 will be turned
                                into string3.  The default behaviour is

                                       bracket-label \*([. \*(.] ", "

       capitalize fields        Convert fields to caps and small caps.

       compatible*              Recognize .R1 and .R2 even when followed by  a
                                character other than space or newline.

       database filename...     Search the bibliographic databases filename...
                                For  each  filename  if  an  index  filename.i
                                created  by indxbib(1) exists, then it will be
                                searched  instead;  each   index   can   cover
                                multiple databases.

       date-as-label* string    string  is a label expression that specifies a
                                string with which to replace the D field after
                                constructing   the   label.    See  the  Label
                                expressions subsection for  a  description  of
                                label  expressions.  This command is useful if
                                you  do  not  want  explicit  labels  in   the
                                reference list, but instead want to handle any
                                necessary  disambiguation  by  qualifying  the
                                date  in some way.  The label used in the text
                                would typically be  some  combination  of  the
                                author  and  date.   In  most cases you should
                                also use  the  no-label-in-reference  command.
                                For example,

                                       date-as-label D.+yD.y%a*D.-y

                                would  attach  a  disambiguating letter to the
                                year part of the D field in the reference.

       default-database*        The default database should be searched.  This
                                is  the  default  behaviour,  so  the negative
                                version of this command is more useful.  refer
                                determines whether the default database should
                                be searched on  the  first  occasion  that  it
                                needs  to  do  a  search.   Thus a no-default-
                                database command must be given before then, in
                                order to be effective.

       discard* fields          When  the  reference is read, fields should be
                                discarded; no string  definitions  for  fields
                                will be output.  Initially, fields are XYZ.

       et-al* string m n        Control  use  of  et al in the evaluation of @
                                expressions  in  label  expressions.   If  the
                                number  of  authors  needed to make the author
                                sequence unambiguous is u and the total number
                                of authors is t then the last t-u authors will
                                be replaced by string provided that t-u is not
                                less  than  m  and  t is not less than n.  The
                                default behaviour is

                                       et-al " et al" 2 3

       include filename         Include filename and interpret the contents as

       join-authors string1 string2 string3
                                This   says   how  authors  should  be  joined
                                together.  When there are exactly two authors,
                                they  will be joined with string1.  When there
                                are more than two authors, all  but  the  last
                                two  will be joined with string2, and the last
                                two authors will be joined with  string3.   If
                                string3   is   omitted,  it  will  default  to
                                string1; if string2 is also  omitted  it  will
                                also default to string1.  For example,

                                       join-authors " and " ", " ", and "

                                will  restore  the  default method for joining

       label-in-reference*      When  outputting  the  reference,  define  the
                                string  [F  to be the reference's label.  This
                                is the  default  behaviour;  so  the  negative
                                version of this command is more useful.

       label-in-text*           For each reference output a label in the text.
                                The  label  will   be   separated   from   the
                                surrounding  text as described in the bracket-
                                label command.  This is the default behaviour;
                                so  the  negative  version  of this command is
                                more useful.

       label string             string is a label expression describing how to
                                label each reference.

       separate-label-second-parts string
                                When  merging  two-part  labels,  separate the
                                second part of the second label from the first
                                label with string.  See the description of the
                                <> label expression.

       move-punctuation*        In the text, move any punctuation at  the  end
                                of  line past the label.  It is usually a good
                                idea to give this command unless you are using
                                superscripted numbers as labels.

       reverse* string          Reverse  the fields whose names are in string.
                                Each field name can be followed  by  a  number
                                which  says  how  many  such  fields should be
                                reversed.  If no number is given for a  field,
                                all such fields will be reversed.

       search-ignore* fields    While  searching  for  keys  in  databases for
                                which no index exists, ignore the contents  of
                                fields.  Initially, fields XYZ are ignored.

       search-truncate* n       Only require the first n characters of keys to
                                be given.  In  effect  when  searching  for  a
                                given  key words in the database are truncated
                                to the maximum of n and the length of the key.
                                Initially n is 6.

       short-label* string      string is a label expression that specifies an
                                alternative (usually shorter) style of  label.
                                This  is  used when the # flag is given in the
                                citation.   When   using   author-date   style
                                labels,  the identity of the author or authors
                                is sometimes clear from the context, and so it
                                may be desirable to omit the author or authors
                                from the label.  The short-label command  will
                                typically   be   used   to   specify  a  label
                                containing  just  a  date   and   possibly   a
                                disambiguating letter.

       sort* string             Sort    references    according   to   string.
                                References will automatically be  accumulated.
                                string  should  be a list of field names, each
                                followed by  a  number,  indicating  how  many
                                fields  with  the  name  should  be  used  for
                                sorting.  + can be used to indicate  that  all
                                the fields with the name should be used.  Also
                                . can  be  used  to  indicate  the  references
                                should  be sorted using the (tentative) label.
                                (The Label  expressions  subsection  describes
                                the concept of a tentative label.)

       sort-adjacent-labels*    Sort  labels  that  are  adjacent  in the text
                                according to their position in  the  reference
                                list.  This command should usually be given if
                                the abbreviate-label-ranges command  has  been
                                given,  or  if the label expression contains a
                                <>  expression.   This  will  have  no  effect
                                unless references are being accumulated.

   Label expressions
       Label  expressions can be evaluated both normally and tentatively.  The
       result of  normal  evaluation  is  used  for  output.   The  result  of
       tentative evaluation, called the tentative label, is used to gather the
       information that normal evaluation needs  to  disambiguate  the  label.
       Label  expressions  specified  by  the  date-as-label  and  short-label
       commands  are  not  evaluated  tentatively.    Normal   and   tentative
       evaluation  are  the  same for all types of expression other than @, *,
       and % expressions.  The description below applies to normal evaluation,
       except where otherwise specified.

       field n
              The n-th part of field.  If n is omitted, it defaults to 1.

              The characters in string literally.

       @      All the authors joined as specified by the join-authors command.
              The whole of each author's name will be used.  However,  if  the
              references  are sorted by author (that is the sort specification
              starts with A+), then authors last names will be  used  instead,
              provided  that  this  does  not introduce ambiguity, and also an
              initial subsequence of the authors may be used  instead  of  all
              the  authors,  again  provided  that  this  does  not  introduce
              ambiguity.  The use of only the last name for the i-th author of
              some  reference  is  considered to be ambiguous if there is some
              other  reference,  such  that  the  first  i-1  authors  of  the
              references  are the same, the i-th authors are not the same, but
              the i-th authors last names are  the  same.   A  proper  initial
              subsequence  of  the  sequence  of authors for some reference is
              considered to be ambiguous if there is  a  reference  with  some
              other  sequence  of authors which also has that subsequence as a
              proper initial subsequence.   When  an  initial  subsequence  of
              authors  is  used,  the  remaining  authors  are replaced by the
              string specified by the et-al command;  this  command  may  also
              specify  additional  requirements  that  must  be  met before an
              initial subsequence can be used.  @ tentatively evaluates  to  a
              canonical  representation of the authors, such that authors that
              compare  equally  for  sorting  purpose  will  have   the   same

       %I     The  serial  number  of the reference formatted according to the
              character following the %.  The serial  number  of  a  reference
              is 1  plus  the number of earlier references with same tentative
              label as this reference.  These expressions tentatively evaluate
              to an empty string.

       expr*  If  there  is another reference with the same tentative label as
              this reference,  then  expr,  otherwise  an  empty  string.   It
              tentatively evaluates to an empty string.

       expr-n The  first  (+)  or  last  (-)  n upper or lower case letters or
              digits of expr.  Troff special characters (such as  \('a)  count
              as  a  single  letter.   Accent  strings are retained but do not
              count towards the total.

       expr.l expr converted to lowercase.

       expr.u expr converted to uppercase.

       expr.c expr converted to caps and small caps.

       expr.r expr reversed so that the last name is first.

       expr.a expr with first names abbreviated.  Note that  fields  specified
              in  the abbreviate command are abbreviated before any labels are
              evaluated.  Thus .a is useful only when you want a field  to  be
              abbreviated in a label but not in a reference.

       expr.y The year part of expr.

              The  part  of  expr  before the year, or the whole of expr if it
              does not contain a year.

              The part of expr after the year, or an empty string if expr does
              not contain a year.

       expr.n The last name part of expr.

              expr1  except  that  if the last character of expr1 is - then it
              will be replaced by expr2.

       expr1 expr2
              The concatenation of expr1 and expr2.

              If expr1 is non-empty then expr1 otherwise expr2.

              If expr1 is non-empty then expr2 otherwise an empty string.

              If expr1 is non-empty then expr2 otherwise expr3.

       <expr> The label is in two parts, which are  separated  by  expr.   Two
              adjacent  two-part labels which have the same first part will be
              merged by appending the second part of the second label onto the
              first  label  separated by the string specified in the separate-
              label-second-parts command (initially, a  comma  followed  by  a
              space);  the  resulting label will also be a two-part label with
              the same first part as before merging, and so additional  labels
              can  be  merged  into  it.   Note that it is permissible for the
              first part to be empty; this  maybe  desirable  for  expressions
              used in the short-label command.

       (expr) The same as expr.  Used for grouping.

       The  above  expressions  are  listed  in  order  of precedence (highest
       first); & and | have the same precedence.

   Macro interface
       Each reference starts with a call to the macro ]-.  The string [F  will
       be  defined to be the label for this reference, unless the no-label-in-
       reference command has been given.   There  then  follows  a  series  of
       string  definitions, one for each field: string [X corresponds to field
       X.  The number register [P is set to 1 if the P field contains a  range
       of pages.  The [T, [A and [O number registers are set to 1 according as
       the T, A and O fields end with one  of  the  characters  .?!.   The  [E
       number  register  will  be set to 1 if the [E string contains more than
       one name.  The reference is followed by a call to the  ][  macro.   The
       first  argument  to  this macro gives a number representing the type of
       the reference.   If  a  reference  contains  a  J  field,  it  will  be
       classified  as  type 1,  otherwise  if  it  contains a B field, it will
       type 3, otherwise if it contains a G or R  field  it  will  be  type 4,
       otherwise if contains a I field it will be type 2, otherwise it will be
       type 0.  The second argument is a symbolic name for  the  type:  other,
       journal-article,  book,  article-in-book  or  tech-report.   Groups  of
       references  that  have  been  accumulated  or  are  produced   by   the
       bibliography  command  are  preceded  by  a  call  to  the ]< macro and
       followed by a call to the ]> macro.


       /usr/dict/papers/Ind  Default database.

       file.i                Index files.

       refer uses temporary files.  See the  groff(1)  man  page  for  details
       where such files are created.


       REFER  If set, overrides the default database.


       indxbib(1), lookbib(1), lkbib(1)


       In   label   expressions,  <>  expressions  are  ignored  inside  .char


       Copyright © 1989-2014 Free Software Foundation, Inc.

       Permission is granted to make and distribute verbatim  copies  of  this
       manual  provided  the  copyright  notice and this permission notice are
       preserved on all copies.

       Permission is granted to copy and distribute modified versions of  this
       manual  under  the  conditions  for verbatim copying, provided that the
       entire resulting derived work is  distributed  under  the  terms  of  a
       permission notice identical to this one.

       Permission  is  granted  to  copy  and  distribute translations of this
       manual into another language, under the above conditions  for  modified
       versions,  except  that  this  permission  notice  may  be  included in
       translations approved by the Free Software Foundation instead of in the
       original English.