@book{79375,
	author = {Zill, Dennis G. and Dewar, Jacqueline M.},
	title = {Essentials of precalculus with calculus previews /},
	publisher = {Jones & Bartlett Learning,},
	year = {2012},
	series = {The Jones & Bartlett Learning series in mathematics},
	address = {Sudbury, MA :},
	edition = {5th ed.}
}