# How to add a letter before the number of citation in the text?

I want \cite to give me [A1] in the text. I cited the reference here \cite{ref1}, which gives the reference as [1]. How to modify it to give me [A1] with A prefixing the number.

\documentclass[a4paper,12pt]{article}
\usepackage{cite}

\begin{document}

I cited the reference here \cite{ref1}, which gives the reference as [1].
How to modify it to give me [A1] with A prefixing the number.

\begin{thebibliography}{99}
\bibitem{ref1} name. 2017 Title of the reference.
\end{thebibliography}

\end{document}

• For that specific reference? Or do you want all references to start with a A? – José Carlos Santos Jul 18 '17 at 7:47
• Hi, @ José Carlos Santos, all reference. – jsxs Jul 18 '17 at 7:48

Redefine \@bibitem and \@biblabel:

\documentclass[a4paper,12pt]{article}
\usepackage{cite}

\makeatletter
\renewcommand\@bibitem[1]{\item\if@filesw \immediate\write\@auxout
{\string\bibcite{#1}{A\the\value{\@listctr}}}\fi\ignorespaces}% <------------
\def\@biblabel#1{[A#1]}% <-------------------
\makeatother

\begin{document}

I cited the reference here \cite{ref1}, \cite{sec}.

\begin{thebibliography}{99}
\bibitem{ref1} name. 2017 Title of the reference.
\bibitem{sec} name. 2017 Title of the reference.
\end{thebibliography}

\end{document}


• Just in case you loaded hyperref and you wonder why the links do not work as expected, you can have a look here. – Axel Krypton Sep 25 '18 at 14:30