Jiyeong Lee A Spatial Access-Oriented Implementation of a 3-D GIS Topological Data Model for Urban Entities. 237-264 2004 8 GeoInformatica 3 http://www.springerlink.com/index/10.1023/B:GEIN.0000034820.93914.d0 db/journals/geoinformatica/geoinformatica8.html#Lee04