edited by Michael W. Alssid and William Kenney
Holt, Rinehart and Winston, 1966
Buku Teks
Clift, Charmian
Collins, 1989
Buku Teks
edited by Greg Crouch, Ted Wheelwright, Ted Wilshire
Penguin Books, 1980
Buku Teks
edited by David W. Orr
University of North Carolina Press, 1979
Buku Teks
Reed, Lawrence W., author
Freedom Institute, 2010
Buku Teks