The product of converse PDL and polymodal K
From Tetherless World Wiki
\begin{bibtex} @article{DBLP:journals/logcom/Wolter00,
author = {Frank Wolter},
title = {The product of converse PDL and polymodal K},
journal = {J. Log. Comput.},
volume = {10},
number = {2},
year = {2000},
pages = {223-251},
bibsource = {DBLP, http://dblp.uni-trier.de}
}
\end{bibtex}
