Harriss, Clement Lowell, 1912-2009
Prentice-Hall, 1967
Buku Teks SO
edited by R.N. Cooper
Penguin Books, 1969
Buku Teks SO
edited by Joseph Seibert & Gorden [i.e. Gordon] Wills
Penguin Books, 1970
Buku Referensi
Hunt, James H.
McGraw-Hill, 1980
Buku Teks
Isaacs, Asher, 1902-1963
Dryden Press, 1952
Buku Teks SO