Mario Sánchez Camilo Jiménez Jorge Villalobos Dirk Deridder Extensibility in Model-Based Business Process Engines. 157-174 2009 TOOLS (47) http://dx.doi.org/10.1007/978-3-642-02571-6_10 conf/tools/47-2009 db/conf/tools/tools47-2009.html#SanchezJVD09