@article { pinheiro12,
	journal = {PLoS ONE},
	keywords = {Game Theory;Multi-Agent Societies;Miscellaneous;},
	number = {e32114},
	title = {From local to global dilemmas in social networks },
	volume = {7 (2)},
	year = {2012},
	author = {Flávio L. Pinheiro and Jorge M. Pacheco and Francisco C. Santos}
}