\input zb-basic
\input zb-ioport
\iteman{io-port 60007569}
\itemau{Zheng, Baihua}
\itemti{Air indexes for spatial databases}
\itemso{Encyclopedia of Database Systems, 71-77 (2009).}
\itemcc{}
\itemut{}
\itemli{doi:10.1007/978-0-387-39940-9\_15}
\end