@conference {Ramos2009,
	title = {A multi-product, multi-depot vehicle routing problem in a reverse logistics system: comparative study of an exact formulation and a heuristic algorithm},
	booktitle = {Livro de actas da 14{\textordmasculine} congresso da APDIO, IO2009},
	year = {2009},
	pages = {195{\textendash}202},
	keywords = {heuristic, milp formulation, reverse logistics, vehicle routing problem},
	author = {Ramos, Tania Rodrigues Pereira and Gomes-Salema, Maria Isabel and Barbosa-povoa, Ana Paula}
}
