Boualem Benatallah Fabio Casati Farouk Toumani Rachid Hamadi Conceptual Modeling of Web Service Conversations. 449-467 2003 conf/caise/2003 CAiSE http://link.springer.de/link/service/series/0558/bibs/2681/26810449.htm db/conf/caise/caise2003.html#BenatallahCTH03