@article {301,
	title = {Complexity Classes in Cellular  Computing with Membranes},
	journal = {Brainstorming Week on Membrane Computing},
	year = {2003},
	month = {5-11/02/2003},
	pages = {270-278},
	address = {Tarragona (Spain)},
	author = {Mario J. P{\'e}rez-Jim{\'e}nez and {\'A}lvaro Romero-Jim{\'e}nez and Fernando Sancho-Caparrini},
	editor = {Matteo Cavaliere and Carlos Mart{\'\i}n-Vide and Gheorghe Paun}
}
