@inproceedings{inproceedings4eb40612,
title   = {Minimum ratio cover of matrix columns by extreme rays of its induced cone},
author = {Freire, Alexandre da Silva and Acuña, Vicente and Crescenzi, Pierluigi and Ferreira, Carlos Eduardo and Lacroix, Vincent and Milreu, P. V and Moreno, E and Sagot, Marie-France},
year = {2012},
doi = {10.1007/978-3-642-32147-4_16},
publisher = {Springer},
booktitle   = {International Symposium on Combinatorial Optimization - ISCO}
}