CQRS, Command Query Responsibility Segregation FAQ

CQRS by Martin Fowler
http://martinfowler.com/bliki/CQRS.html

Introducing the Command Query Responsibility Segregation Pattern from MSDN
http://msdn.microsoft.com/en-us/library/jj591573.aspx

C# code exmaple: LIntroduction to CQRS
http://www.codeproject.com/Articles/555855/Introduction-to-CQRS