@article{
author = {Maria-Florina Balcan and  Avrim Blum},
title = {Approximation Algorithms and Online Mechanisms for Item Pricing},
journal = {Theory of Computing},
year = {2007},
volume = {3},
number = {9},
pages = {179-195},
publisher = {Theory of Computing},
eprint = {toc:v003/a009},
URL = {http://www.theoryofcomputing.org/articles/main/v003/a009},
}