Christoph Eichner Hans Fleischhack Roland Meyer Ulrik Schrimpf Christian Stehno Compositional Semantics for UML 2.0 Sequence Diagrams Using Petri Nets. 133-148 2005 conf/sdl/2005 SDL Forum http://dx.doi.org/10.1007/11506843_9 db/conf/sdl/sdl2005.html#EichnerFMSS05