@book{56500,
	author = {Snell, Foster Dee. and Snell, Cornelia T.},
	title = {Colorimetric methods of analysis},
	publisher = {Van Nostrand,},
	year = {1948-},
	address = {Princenton :},
	edition = {3 ed.},
	note = {v.2A 1ra. ed. de 1959}
}