Software Architecture , software flexibility , extensibility and maintainability

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• http://www.cs.cmu.edu/~acme/docs/language_overview.html
• software architecture evaluation

http://www.win.tue.nl/oas/architecting/aimes/papers/Scenario-Based%20SWA%20Evaluation%20Methods.pdf

• software flexibility , extensibility and maintainability

http://blog.adaptivesoftware.biz/2006/09/big-three-flexibility-extensibility.html