Exploiting a page-level upper bound for multi-type nearest neighbor queries.

Xiaobin Ma Shashi Shekhar Hui Xiong Pusheng Zhang Exploiting a page-level upper bound for multi-type nearest neighbor queries. 179-186 2006 conf/gis/2006 GIS http://doi.acm.org/10.1145/1183471.1183501 db/conf/gis/gis2006.html#MaSXZ06