@book{4420,
	author = {Freund, John E. and Walpole, Ronald E.},
	title = {Mathematical statistics /},
	publisher = {Prentice-Hall ;},
	year = {c1987 [reprinted].},
	address = {Englewood Cliffs, N.J. :},
	edition = {4th ed.},
	note = {Includes index.}
}