Rotenberg, Daniel L., author
Little,Brown and Company, 1967
Buku Teks
Tiffany, Lawrence P., author
Little, Brown, 1967
Buku Teks
Richie, Beth E
Routledge, 1996
Buku Teks
Mills, C. Wright, author
Oxford University Press, 1951
Buku Teks
Wear, George F.
Oxford University Press, 1950
Buku Teks