R. Villarroel, E. Fernández-Medina, and M. Piattini. CAiSE Workshops (1), page 189-198. Faculty of Computer Science and Information Technology, Riga Technical University, Riga, Latvia, (2004)
A. Urrutia, J. Galindo, L. Jiménez, and M. Piattini. IFIP TC8 WCC ISS, volume 214 of IFIP Advances in Information and Communication Technology, page 201-217. Springer, (2006)