explicit theory qualifier for session "HOL-Proofs": its theory name space overlaps with session "HOL", even for further imports;
\index{model checking example|(}%
\index{lfp@{\texttt{lfp}}!applications of|see{CTL}}
\input{Base.tex}
\input{PDL.tex}
\input{CTL.tex}
\index{model checking example|)}