@article {Cerdeira2005,
	title = {Requiring connectivity in the set covering problem},
	journal = {Journal of Combinatorial Optimization},
	volume = {9},
	number = {1},
	year = {2005},
	note = {n/a},
	pages = {35-47},
	abstract = {n/a},
	author = {Cerdeira, J.O. and Pinto, L.S.}
}
