Katerina Pokozy-Korenblat Corrado Priami Toward Extracting ?-calculus from UML Sequence and State Diagrams. 51-72 2004 101 Electr. Notes Theor. Comput. Sci. http://dx.doi.org/10.1016/j.entcs.2004.09.007 db/journals/entcs/entcs101.html#Pokozy-KorenblatP04