Pergamon Press, 1980
Buku Teks
Moore, James M.
McMillan, 1962
Buku Teks
Apple, James MacGregor, 1915-1978
John Wiley & Sons, 1977
Buku Teks
Ireson, William Grant, 1914-
Prentice-Hall, 1959
Buku Teks
Apple, James MacGregor, 1915-1978
The Ronald Press , 1950
Buku Teks