Kosso, Peter
Cambridge University Press, 1992
Buku Teks SO
Losee, John
Oxford University Press, 1980
Buku Teks SO
edited by Richard Boyd, Philip Gasper, and J. D. Trout
Bradford Book, 1997
Buku Teks SO
Stathis Psillos, Martin Curd, editor
Routledge, 2008
Buku Teks
Cohen, Morris R.
Henry Holt, 1949
Buku Teks SO