\input zb-basic
\input zb-ioport
\iteman{io-port 60007700}
\itemau{}
\itemti{Topological data structure}
\itemso{Encyclopedia of Database Systems, 3140 (2009).}
\itemcc{}
\itemut{}
\itemli{doi:10.1007/978-0-387-39940-9\_3845}
\end