Hans Weigand Paul Johannesson Birger Andersson Maria Bergholtz Value-Based Service Modeling and Design: Toward a Unified View of Services. 410-424 2009 CAiSE http://dx.doi.org/10.1007/978-3-642-02144-2_33 conf/caise/2009 db/conf/caise/caise2009.html#WeigandJAB09