@book{100561,
	author = {Walsh, W. H.},
	title = {Introducción a la filosofía de la historia},
	publisher = {Siglo Veintiuno Editores},
	year = {1971.},
	series = {Teoria y critica.},
	address = {México},
	edition = {3ra. ed.},
	note = {Translation of the 3d rev. ed. of An introduction to philosophy of history.}
}