@book{5020,
	author = {Ratto, Jorge A. and Gabba, Pablo J.},
	title = {Ciencias para maestros},
	publisher = {Marymar},
	year = {1981},
	series = {El maestro en su acción cotidiana. Desarrollos curriculares},
	address = {Buenos Aires},
	edition = {4ª ed.}
}