1Open GIS Consortium Inc.,OpenGIS Simple Features Specification For SQL. http://www.opengeospatial.org/docs/99-049. pdf,1999.
2Marios Hadjieleftheriou, Erik G. Hoel, Vassilis J. Tsotras. SalL:A Spatial Index Library for Efficient Application Integration. Geoinformatica,DEC 2005.9(4):367-389.
3Caduff, David. Egenhofer, Max J. Geo-mobile queries: Sketch-based queries in mobile GIS-environments, Lecture Notes in Computer Science, v 3833,Web and Wireless Geographical Information Systems-5th International Workshop, W2GIS 2005, Proceedings,2006:143-154.
4Tsou, Ming-Hsiang. "Integrated mobile GIS and wireless intemet map servers for environmental monitoring and management". Cartography and Geographic Information Science,v31,n3,July, 2004:153-165.
5Clarke, Keith C. "Mobile mapping and geographic information systems". Cartography and Geographic Information Science, v31,n3,July,2004:131-136.