The kernel-solvability of perfect graphs was first proved by Boros and Gurvich, and later Aharoni andHolzmangave a shorter proof. Bothproofswere based on Scarf’s Lemma. In this note we show that a very simple proof can be given using a polyhedral version of Sperner’s Lemma. In addition, we extend the Boros–Gurvich theorem to h-perfect graphs and to a more general setting. © 2009 Elsevier B.V. A...
