Edgar, Donald E.
Prentice-Hall, 1980
Buku Teks SO
Benson, Leonard
Random House , 1968
Buku Teks SO
edited Scott G. Mcnall
Little, Brown, 1968
Buku Teks SO
Wright, Charles Robert
Random House, 1975
Buku Teks SO
edited by Scott G. McNall
Little, Brown and Company, 1968
Buku Teks SO