@book{198189,
	author = {Labow, William},
	title = {Principios del cambio lingüístico},
	publisher = {Gredos},
	year = {1996},
	address = {Madrid},
	note = {Trad. P. Martín Butragueño; la Biblioteca sólo posee el v. 1: Factores internos}
}