S. Dustdar, H. Gall, R. Schmidt:
"Web Services for Groupware";
in: "Service-Oriented Software System Engineering", issued by: Zoran Stojanovic, Ajantha Dahanayake; Idea Group Publishing, USA, 2005, ISBN: 1-59140-426-6, 353 - 370.
http://aleph.ub.tuwien.ac.at/F?base=tuw01&func=find-c&ccl_term=AC05936367