@book{44450,
	author = {Piaget, Jean and Quintanilla, Miguel A.},
	title = {Problemas de psicología genética / },
	publisher = {Editorial Ariel ,  },
	year = {1980.},
	series = {Ariel quincenal-},
	address = {Barcelona : },
	edition = {4a. ed.},
	note = {Incluye índice. }
}