Dmytro Dyachuk Ralph Deters Ensuring Service Level Agreements for Service Workflows. 333-340 2008 IEEE SCC (2) http://doi.ieeecomputersociety.org/10.1109/SCC.2008.117 conf/IEEEscc/2008 db/conf/IEEEscc/scc2008.html#DyachukD08