\usepackage[bookmarks=true]{hyperref}
\usepackage{makeidx}
%\usepackage{booktabs}
-\usepackage{pstcol}
+%\usepackage{pstcol}
\usepackage{pst-node}
\usepackage{graphicx}
\usepackage{babel}
%\bibliography{biblio}
\printindex
-\bibliographystyle{alpha}
+\bibliographystyle{ieeetr}
\bibliography{biblio}
\end{document}