Lee, Simon
Oxford University Press , 1986
Buku Teks
Pincoffs, Edmund L.
California Wadsworth , 1991
Buku Teks
Finnis, John, author
Oxford Univesity Press, 2011
Buku Teks
Bishin, William
Foundation Press, 1972
Buku Teks
Raz, Joseph, author
Oxford Univesity Press, 2009
Buku Teks