@book{180612,
	author = {Sobel, Max A. and Lerner, Norbert.},
	title = {Precalculus mathematics},
	publisher = {Prentice-Hall},
	year = {c1995.},
	address = {Englewood Cliffs, New York},
	edition = {5th ed.},
	note = {Includes index.}
}