Erling Onstein, Assistant Sverre Stikbakke. "EXPLORING SUBSET PROFILE AND VALIDATION PROCEDURES OF GEOGRAPHICAL MARKUP LANGUAGE (GML) FOR 3D AREAL PLAN INFORMATION." SGEM International Multidisciplinary Scientific GeoConference EXPO Proceedings; 17th International Multidisciplinary Scientific GeoConference SGEM2017, Informatics, Geoinformatics and Remote Sensing (2017): 883-894. https://doi.org/10.5593/sgem2017/21/s08.112