Volkmar Pipek Mary Beth Rosson Boris E. R. de Ruyter Volker Wulf End-User Development, 2nd International Symposium, IS-EUD 2009, Siegen, Germany, March 2-4, 2009. Proceedings 5435 2009 http://dx.doi.org/10.1007/978-3-642-00427-8 978-3-642-00425-4 IS-EDU Lecture Notes in Computer Science Springer db/conf/iseud/iseud2009.html