\documentclass{article} 
\usepackage{graphicx}
\usepackage{subfigure} 
\begin{document}

Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Proin euismod.
Proin commodo consectetuer erat. Nam ullamcorper justo. Vestibulum eget
nisl. Sed neque arcu, eleifend vitae, ultricies non, consequat quis, mi.
Sed blandit. Vestibulum nonummy, dolor vitae convallis molestie, justo
libero molestie magna, ut faucibus justo neque id massa. Sed auctor.

\begin{figure}[h]
\begin{center}
\subfigure[Big]{\includegraphics[width=0.3\textwidth]{fig_test.png}}\quad
\subfigure[Medium]{\includegraphics[width=0.25\textwidth]{fig_test.png}}\quad
\subfigure[Small]{\includegraphics[width=0.2\textwidth]{fig_test.png}}
\end{center}
\caption{Three subfigures}
\end{figure} 

Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Proin euismod.
Proin commodo consectetuer erat. Nam ullamcorper justo. Vestibulum eget
nisl. Sed neque arcu, eleifend vitae, ultricies non, consequat quis, mi.
Sed blandit. Vestibulum nonummy, dolor vitae convallis molestie, justo
libero molestie magna, ut faucibus justo neque id massa. Sed auctor.

\begin{figure}[h]
\begin{center}
\subfigure[Big]{\includegraphics[width=0.3\textwidth]{fig_test.png}}\quad
\subfigure{\includegraphics[width=0.25\textwidth]{fig_test.png}}\quad
\subfigure[Small]{\includegraphics[width=0.2\textwidth]{fig_test.png}}
\end{center}
\caption{Testing numbering of subfigures}
\end{figure} 

Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Proin euismod.
Proin commodo consectetuer erat. Nam ullamcorper justo. Vestibulum eget
nisl. Sed neque arcu, eleifend vitae, ultricies non, consequat quis, mi.
Sed blandit. Vestibulum nonummy, dolor vitae convallis molestie, justo
libero molestie magna, ut faucibus justo neque id massa. Sed auctor.


\end{document}