@book{1092,
	author = {PURCELL, EDWING J. and VARBERG, DALE.},
	title = {CALCULO CON GEOMETRIA ANALITICA/ },
	publisher = {PRENTICE - HALL HISPANOAMERICANA},
	year = {1987},
	address = {MEXICO: },
	edition = {4},
	note = {INCLUYE INDICE}
}