Shahar Dobzinski, Noam Nisan, Michael Schapira. Approximation algorithms for combinatorial auctions with complement-free bidders. In Harold N. Gabow, Ronald Fagin, editors, Proceedings of the 37th Annual ACM Symposium on Theory of Computing, Baltimore, MD, USA, May 22-24, 2005. pages 610-618, ACM, 2005. [doi]
Abstract is missing.