Affiliation: | 1. Department of Mathematics and Industrial Engineering and GERAD, École Polytechnique de Montréal, C.P. 6079, Succursale Centre-ville, Montréal, Qué., Canada H3C 3A7;2. College of Business Administration, University of Missouri-St. Louis, 8001 Natural Bridge Road, St. Louis, MO 63121-4499, USA |