Bodner, George M.
John Wiley & Sons, 1995
Buku Teks SO
Sackheim, George I.
Macmillan, 1977
Buku Teks SO
Pimentel, George C.
Holden-Day, 1971
Buku Teks SO
Oxtoby, David W.
Thomson, Brooks/Cole, 2003
Buku Teks SO
Brown, Theodore L.
Prentice-Hall, 1977
Buku Teks SO