H. Klabi, K. Mellouli, S. Mellouli, and M. Rekik. Communications and Information Technology (ICCIT), 2012 International Conference on, page 291-296. (June 2012)
G. Robles, J. Amor, J. Gonzalez-Barahona, and I. Herraiz. Proc. Int'l Workshop on Principles of Software Evolution (IWPSE), page 165 -- 174. Lisbon, IEEE Computer Society Press, (September 2005)