TY - JOUR AU - Tilahun, Surafel Luleseged TI - Convex Grey Optimization JO - RAIRO - Operations Research - Recherche Opérationnelle PY - 2019 SP - 339 EP - 349 VL - 53 IS - 1 PB - EDP-Sciences UR - http://www.numdam.org/articles/10.1051/ro/2018088/ DO - 10.1051/ro/2018088 LA - en ID - RO_2019__53_1_339_0 ER -