biblatex: is it possible to add a text directly after the reference number (without a comma)?

Question

I'd like to add a certain marker after some bibliographic entries, e. g. superscript star *.

It should appear directly after the references number and should not be separated by a comma (as normal suffixes are).

Remark: I also need the normal suffixes for giving page numbers, so how could I achieve that without changing the standard behavior of \cite[prefix][suffix]{citekey}?

example:

\documentclass{scrbook}

\begin{filecontents*}{mybib7.bib}

@MISC{Caesar,
  author = {Caesar, Gaius J.},
  title = {title},
  year = {45BC},
}

@MISC{Cicero,
  author = {Cicero, Marcus T.},
  title = {title},
  year = {44BC},
}

\end{filecontents*}

\newcommand{\WW}{\textsuperscript{*}}

\usepackage[natbib=true, style=numeric-comp, backend=bibtex8, defernumbers, useprefix, maxnames=99, maxcitenames=3]{biblatex}  % f¸r bessere Literaturverzeichnisse
\renewcommand{\bibfont}{\normalfont\small}
\renewcommand\multicitedelim{\addsemicolon\space}


\usepackage{csquotes} 

\bibliography{mybib7}

\begin{document}

\cites[][\WW{}]{Caesar}[][p.~13]{Cicero}

I wish it would look like that: [1\WW{}; 2, p.~13]

\nocite{*}
\printbibliography

\end{document}

Answer 1

Here's one way to do it:

• Define a new boolean citewithstar (which defaults to false).

• Change the definition of the cite bibmacro so that a superscript star is added after the label number if citewithstar is true.

• Define a macro \starnext that will set citewithstar to true for the next citation key.

• Add \starnext in the prenote optional argument of the respectice citation command.

So far, there's one drawback: Adding \starnext in the prenote optional argument of the first/only citation key will produce an unwanted additional space. In this case, add \starnext before the citation command (see my example).

Note: You don't have to use "p.~13" in postnote optional arguments -- biblatex will assume that "13" is a page number and apply the correct formatting.

\documentclass{article}

\usepackage{biblatex}

\renewcommand*{\multicitedelim}{\addsemicolon\space}

\newbool{citewithstar}

\renewbibmacro*{cite}{%
  \printtext[bibhyperref]{%
    \printfield{prefixnumber}%
    \printfield{labelnumber}%
    \ifbool{citewithstar}{\textsuperscript{*}}{}% ADDED
    \ifbool{bbx:subentry}
      {\printfield{entrysetcount}}
      {}}}

\newcommand*{\starnext}{%
  \AtNextCitekey{\booltrue{citewithstar}}%
}

\usepackage{filecontents}

\begin{filecontents*}{\jobname.bib}
@MISC{Caesar,
  author = {Caesar, Gaius J.},
  title = {title},
  year = {45BC},
}
@MISC{Cicero,
  author = {Cicero, Marcus T.},
  title = {title},
  year = {44BC},
}
\end{filecontents*}

\addbibresource{\jobname.bib}

\begin{document}

\starnext\cites{Caesar}[13]{Cicero}

\cites{Caesar}[\starnext][13]{Cicero}

\printbibliography

\end{document}

If you'd like to specify the symbol in the label number suffix, a control sequence can take the place of citewithstar.

\documentclass{article}
\usepackage[american]{babel}
\usepackage{csquotes}
\usepackage[style=numeric-comp,sorting=none]{biblatex}
\usepackage[colorlinks]{hyperref}

\renewcommand*{\multicitedelim}{\addsemicolon\space}

\DeclareFieldFormat{labelnumber}{\mkbiblabelsuffix{#1}}

\newrobustcmd*{\mkbibsuffix}[1]{%
  \csgdef{cbx:suffix}{#1}}

\newrobustcmd*{\mkbiblabelsuffix}[1]{%
  \ifcsundef{cbx:suffix}
    {#1}
    {#1\mkbibsuperscript{\csuse{cbx:suffix}}%
     \global\csundef{cbx:suffix}}}

\addbibresource{biblatex-examples.bib}
\begin{document}
\mkbibsuffix{\dag}\cite[10--15]{companion}
\mkbibsuffix{*}\cites[10--15]{companion}[e.g.\mkbibsuffix{**}][]{ctan}{markey}{knuth:ct}
\mkbibsuffix{\ddag}\cites{companion}{ctan,markey,knuth:ct}
\printbibliography
\end{document}

Answer 2

The label number suffix can be specified in the postnote argument, but we need some way of distinguishing it from the actual postnote.

Here we wrap the suffix in parentheses and put it before any postnote. Other delimiters could be used, just not square and curly brackets - they either interfere with the arguments of the citation command or get processed out of the postnote field.

\documentclass{article}
\usepackage[american]{babel}
\usepackage{csquotes}
\usepackage[style=numeric-comp,sorting=none]{biblatex}
\usepackage[colorlinks]{hyperref}

\renewcommand*{\multicitedelim}{\addsemicolon\space}

\renewbibmacro*{postnote}{%
  \iffieldundef{postnote}{}{\printfield{postnote}}}

\DeclareFieldFormat{postnote}{\mkpostnote#1\relax}

\makeatletter

\newrobustcmd*{\mkpostnote}{%
  \@ifnextchar(%)
    {\mkpostnote@i}
    {\mkpostnote@i()}}

\def\mkpostnote@i(#1){%
  \ifblank{#1}{}{\mkbibsuperscript{#1}}%
  \@ifnextchar\relax{}{\mkpostnote@ii}}

\def\mkpostnote@ii#1\relax{%
  \postnotedelim%
  \mkpageprefix[pagination]{#1}}

\makeatother

\addbibresource{biblatex-examples.bib}
\begin{document}
\subsection*{Without label number suffix}
\cite[See][]{companion}
\cite[See][10]{companion}
\cite[See][10--15]{companion}
\cite[See][10--15 and the last section]{companion}
\cites[10--15]{companion}[e.g.][]{ctan}[10--15]{markey}[10]{knuth:ct}
\cite[See][]{companion,ctan,markey,knuth:ct}
\subsection*{With label number suffix}
\cite[See][(\dag)]{companion}
\cite[See][(\dag)10]{companion}
\cite[See][(\dag)10--15]{companion}
\cite[See][(\dag) 10--15 and the last section]{companion}
\cites[(*)10--15]{companion}[e.g.][(**)]{ctan}[10--15]{markey}[10]{knuth:ct}
\cites(See)()[(\ddag)]{companion}{ctan,markey,knuth:ct}
\printbibliography
\end{document}

For reference here's an excerpt of the same document without any changes to the postnote format.