1. Amazon web services, http://www.amazon.com/AWS-home-page-Money/b?ie=UTF8&node=3435361
2. Links, http://groups.inf.ed.ac.uk/links/
3. Microsoft Linq, http://msdn.microsoft.com/data/ref/linq/
4. Service component architecture, http://www-128.ibm.com/developerworks/library/specification/ws-sca/
5. Atkinson, M.P., Buneman, O.P.: Types and persistence in database programming languages. ACM Computing Surveys 19(2), 105–170 (1987)