@Article{ZenkRiesPicoDeWeCostBent09,
author = {Rico Zenklusen and Bernard Ries and Christophe Picouleau and Dominique de Werra and Marie-Christine Costa and C\'edric Bentz },
title = {Blockers and transversals},
journal = {Discrete Mathematics},
volume = {309},
number = {13},
pages = {4306-4314},
doi = {10.1016/j.disc.2009.01.006},
year = {2009}
}