edited by G. Goodwin
Cambridge University Press, 1958
Buku Teks
Cambridge University Press, 1965
Buku Teks
Palmer, Alan, author
Penguin Books, 1981
Buku Referensi
Tosh, John, author
Longman , 1991
Buku Teks
edited by H. H. Dodwell
University Press, 1929
Buku Teks