A. Lucia, E. Pompella, and S. Stefanucci. Proceedings of the 14th international conference on Software engineering and knowledge engineering, page 409--416. New York, NY, USA, ACM, (2002)
Y. Kultur, B. Turhan, and A. Bener. Proceedings of the 16th ACM SIGSOFT International Symposium on Foundations of software engineering, page 330-338. ACM, (2008)