@article{Lehmann_2006,
title={Combinatorial auctions with decreasing marginal utilities},
volume={55},
ISSN={0899-8256},
url={http://dx.doi.org/10.1016/j.geb.2005.02.006},
DOI={10.1016/j.geb.2005.02.006},
number={2},
journal={Games and Economic Behavior},
publisher={Elsevier BV},
author={Lehmann,
Benny and Lehmann,
Daniel and Nisan,
Noam},
year={2006},
month=may,
pages={270–296} }