Burke, Peter
Princeton University Press, 1986
Buku Teks SO
Hale, John R.
Time-Life International, 1969
Buku Teks SO
edited by John Caldwell, Edward Olleson and Susan Wollenberg
Oxford University Press, 1990
Buku Teks SO
Lucas, Henry S.
Harper and Row, 1960
Buku Teks SO
Ackerman, James S.
MIT Press, 1991
Buku Teks SO