W. van der Aalst. Proceedings of the 33rd International Conference on Application and Theory of Petri Nets, page 72--91. Berlin, Heidelberg, Springer-Verlag, (2012)
O. Hassan, M. Farag, and M. MohieEl-Din. Proceedings of the 10th WSEAS International Conference on Applied Informatics and Communications, and 3rd WSEAS International Conference on Biomedical Electronics and Biomedical Informatics, page 275--282. Stevens Point, Wisconsin, USA, World Scientific and Engineering Academy and Society (WSEAS), (2010)