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2. The OWL Services Coalition. OWL-S: Semantic Markup for Web Services,
http://www.daml.org/services/owl-s/1.0/owl-s.pdf
3. World Wide Web Consortium (W3C). Web Ontology Language (OWL),
http://www.w3.org/2004/OWL/
4. Microsoft Corporation. Architecture of Windows Media Rights Manager (May 2004),
http://www.microsoft.com/windows/windowsmedia/howto/articles/drmarchitecture.aspx
5. RealNetworks, Inc. Media Commerce suite,
http://www.realnetworks.com/products/commerce/description.html