R. Kazman, L. Bass, G. Abowd, and M. Webb. Software Engineering, 1994. Proceedings. ICSE-16., 16th International Conference on, page 81--90. (May 1994)
F. Solms, P. Rooyen, and J. Kunicki. Communications and Signal Processing, 1994. COMSIG-94., Proceedings of the 1994 IEEE South African Symposium on, page 11--15. (October 1994)