TY - JOUR AU - Gangbo, Wilfrid AU - Oliker, Vladimir TI - Existence of optimal maps in the reflector-type problems JO - ESAIM: Control, Optimisation and Calculus of Variations PY - 2007 SP - 93 EP - 106 VL - 13 IS - 1 PB - EDP-Sciences UR - http://www.numdam.org/articles/10.1051/cocv:2006017/ DO - 10.1051/cocv:2006017 LA - en ID - COCV_2007__13_1_93_0 ER -