Konstantinos G. Kouskouras Alexander Chatzigeorgiou George Stephanides Facilitating software extension with design patterns and Aspect-Oriented Programming. 1725-1737 2008 81 Journal of Systems and Software 10 http://dx.doi.org/10.1016/j.jss.2007.12.807 db/journals/jss/jss81.html#KouskourasCS08