\documentclass[twoside]{article}

\usepackage{hevea}
\usepackage{a4}
\usepackage{calc}
\usepackage{multicol}
\usepackage{tabularx}
\usepackage{makeidx}
\usepackage{ifthen}
\usepackage{fancyheadings}
\ifpdf
	\usepackage[pdftex]{graphicx}
	\usepackage[pdftex=true]{hyperref}
\else
	\usepackage[dvips]{graphics}
	\usepackage{epsfig}
\fi


