edited by Chaerles W. Eliot
P.F. Collier & Son, 1959
Buku Referensi
Smith, Adam, author
Modern Library, 1937
Buku Referensi
Wight, Jonathan B.
Prentice-Hall, 2002
Buku Teks
West, E.G., author
Airlington House, 1969
Buku Teks
Smith, Adam, author
Modern Library, 2000
Buku Teks