\begin{toc}
\tocitem {ipr0.html#@l10}{Title Page}
\tocitem {ipr1.html#@l11}{A Dialog}
\begin{toc}
\tocitem {ipr10.html#@l110}{Summary}
\end{toc}
\tocitem {ipr2.html#@l12}{A few other facts}
\tocitem {ipr3.html#@l13}{Copyright of UIs}
\tocitem {ipr4.html#@l14}{Patents}
\tocitem {ipr5.html#@l15}{Exercises}
\tocitem {ipr6.html#@l16}{Philosphical Note}
\begin{toc}
\tocitem {ipr60.html#@l160}{Optional Exercises}
\end{toc}
\tocitem {ipr7.html#@l17}{References}
\end{toc}