2Michael F G, Max J E, Robin F. Interoperating GISs. http://ncgia.ucsb.edu/conf/interop97/report.html,1997.
3UCGIS. Interoperability of Geographic Information. http://www.ucgis.org, 1997.
4Bishr Y. Semantic Aspects of Interoperable GIS:[Ph. D. Dissertation] . Amsterdam: International Institute for Aerospace Survey and Earth Sciences, 1997.
5Vckovski A. Interoperable and Distributed Processing in GIS. London: Taylor & Francis,1998.
6Buehler K,McKee L. The Open GIS Guide: Introduction to Interoperable Geoprocessing. Open GIS Consortium Inc, 1996.