Alistair J. Edwardes Ross S. Purves A Theoretical Grounding for Semantic Descriptions of Place. 106-120 2007 W2GIS http://dx.doi.org/10.1007/978-3-540-76925-5_8 conf/w2gis/2007 db/conf/w2gis/w2gis2007.html#EdwardesP07