Hoda Mokhtar Jianwen Su QUESTO: A Query Language for Uncertain and Exact Spatio-temporal Objects. 184-198 2008 ADBIS http://dx.doi.org/10.1007/978-3-540-85713-6_14 conf/adbis/2008 db/conf/adbis/adbis2008.html#MokhtarS08