1. ANSI, 1995. Information Retrieval Application Service Definition and Protocol Specification for Open Systems Interconnection. ANSI/NISO Z39.50-1995 (ISO 23950), American National Standards Institute (ANSI), available at http://lcweb.loc.gov/z3950/agency/document.html.
2. Beaujardière, J., 2002. Web Map Server Implementation Specification. Version 1.1.1. OpenGIS project document 01-068r3, Open GIS Consortium Inc.
3. Booth, D., Haas, H., McCabe, F., Newcomer, E., Champion, M., Ferris, C., Orchard, D., 2004. Web Services Architecture. W3C Working Group Note 11 February 2004, W3C, http://www.w3.org/TR/2004/NOTE-ws-arch-20040211/.
4. Bray, T., Paoli, J., Sperberg-McQueen, C.M., Maler, E., 2000. Extensible Markup Language (XML) 1.0, second ed. W3C Recommendation 6 October 2000, W3C, http://www.w3.org/TR/2000/REC-xml-20001006.
5. Buehler, K., McKee, L., 1996. The OpenGIS Guide. Introduction to Interoperable Geoprocessing. Part I of the Open Geodata Interoperability Specification (OGIS). OGIS TC Document 96-001, OGIS Project 6 Technical Committee of the OpenGIS Consortium Inc.