\documentclass[a4paper]{article}
\usepackage{graphicx}
\usepackage{ifpdf}
\ifpdf
\else
  \special{header=verdana.pfa}
  \special{header=verdanab.pfa}
\fi

\begin{document}

\noindent{\centerline{\includegraphics[width=4cm]{CLCG-fig}}}

\noindent{\centerline{\includegraphics[width=8cm]{CLCG-fig}}}

\noindent{\centerline{\includegraphics[width=12cm]{CLCG-fig}}}

\noindent{\centerline{\includegraphics[width=16cm]{CLCG-fig}}}

\end{document}
