@book{78495,
	author = {Zill, Dennis G. and Wright, Warren S.},
	title = {Multivariable calculus /},
	publisher = {Jones and Bartlett Publishers,},
	year = {2011},
	series = {The Jones and Bartlett Publishers series in mathematics},
	address = {Sudbury, Mass. :},
	edition = {4th ed.},
	note = {Includes index}
}