@book{133090,
	author = {Michels, Robert},
	title = {Los partidos políticos},
	publisher = {Amorrortu Editores},
	year = {1972},
	address = {Buenos Aires},
	edition = {2. ed.},
	note = {Translation of : Political Parties. A Sociological Study of the Oligarchical Tendencies of Modern Democracy.}
}