@article {3780, title = {A graphical formalism for mixed multi-unit combinatorial auctions}, journal = {Autonomous Agents and Multi Agent Systems}, volume = {20}, year = {2010}, month = {May}, pages = {342-368}, chapter = {342}, author = {Andrea Giovannucci and Jes{\'u}s Cerquides and U. Endriss and Juan A. Rodr{\'\i}guez-Aguilar} }