\begin{overpic}[width=0.49\textwidth]{tour-19}
\put(1,74){\colorbox{white}{(\sublabel{tour-19}) \href{http://dream.misasa.okayama-u.ac.jp/?q=20210114030310-631569}{tour-19}}}
%%(\subref{tour-19}) \href{tour-19}
\color{red}
\end{overpic}