Gero Decker Oliver Kopp Frank Leymann Kerstin Pfitzner Mathias Weske Modeling Service Choreographies Using BPMN and BPEL4Chor. 79-93 2008 CAiSE http://dx.doi.org/10.1007/978-3-540-69534-9_6 conf/caise/2008 db/conf/caise/caise2008.html#DeckerKLPW08