Decision Support Systems . Collaborative Models and Approaches in Real Environments : Euro Working Group Workshops, EWG-DSS 2011, London, UK, June 23-24, 2011, and Paris, France, November 30 - December 1, 2011, Revised Selected and Extended Papers - Jorge E. Hernández, Pascale Zarate, Fátima Dargam, Boris Deliba.i., Shaofeng Liu, Rita Ribeiro ((Lecture Notes in Business Information Processing))