@book{183966,
	author = {Echave, Delia Teresa and Urquijo , María Eugenia .},
	title = {Lógica, proposición y norma},
	publisher = {Editorial Astrea},
	year = {1980.},
	series = {Colección Filosofía y derecho},
	address = {Buenos Aires},
	edition = {1ra ed.}
}