\begin{overpic}[width=0.49\textwidth]{ref_gl_NISTs}
\put(1,74){\colorbox{white}{(\sublabel{ref_gl_NISTs}) \nolinkurl{http://dream.misasa.okayama-u.ac.jp/?q=20110329163643-654-794}{ref_gl_NISTs}}}
%%(\subref{ref_gl_NISTs}) \nolinkurl{ref_gl_NISTs}
\color{red}
\end{overpic}