NAME
refer - preprocess bibliographic references for groff
SYNOPSIS
refer [ -benvCPRS ] [ -a n ] [
-c fields ] [ -f n ] [ -i
fields ] [ -k field ] [ -l m,n ]
[ -p filename ] [ -s fields ] [
-t n ] [ -B field.macro ]
[ filename... ]
It is possible to have whitespace between a command line option
and its parameter.
DESCRIPTION
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 commands.
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).
OPTIONS
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
- -cfields
- capitalize fields
- -fn
- label %n
- -ifields
- search-ignore fields
- -k
- label Lti%a
- -kfield
- label fieldti%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
- -pfilename
- 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
- -Bfield.macro
- 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.
USAGE
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
- 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
- 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 used.
- 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
reference.
- 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.
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 used.
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 two.
Citations
The format of a citation is
- .[opening-text
flags keywords
fields
.]closing-text
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 recognized:
- #
- 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
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
s extends to the next s that is not followed by
another s. If there is no such s the word extends to
the end of the line. Pairs of s in a word beginning with
s collapse to a single s. Neither # nor
; are recognized inside ss. 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. u+2n
-
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 construction.
- 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
-
- .[
$LIST$
.]
is encountered, after all input files hve been processed, and
whenever .R1 line is recognized.
- annotate* field string
- field is an annotation; print it at the end of the
reference as a paragraph preceded by the line
-
- .string
If macro 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...
-
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 commands.
-
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 authors.
- 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
-
- field n
- The n-th part of field. If n is omitted,
it defaults to 1.
- 'string'
- 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 representation.
- %n
-
- %a
- %A
- %i
- %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
-
- 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.
- expr.+y
- The part of expr before the year, or the whole of
expr if it does not contain a year.
- expr.-y
- 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.
- expr1tiexpr2
- 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.
- expr1|expr2
- If expr1 is non-empty then expr1 otherwise
expr2.
- expr1&expr2
- If expr1 is non-empty then expr2 otherwise an
empty string.
- expr1?expr2:expr3
- 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.
FILES
u+2n
- /usr/dict/papers/Ind Default database.
- file.i
- Index files.
SEE ALSO
indxbib(1),
lookbib(1),
lkbib(1)
BUGS
In label expressions, <> expressions are
ignored inside .char expressions.