Watt, William Montgomery
At The Clarendon Press, 1953
Buku Teks SO
Mccarthy, Cormac
Vintage International, 2006
Buku Teks SO
Artikel Jurnal
Hutchinson, Alfred
John Day, 1960
Buku Teks SO
Davison, Frank Dalby, 1983-1970
Angus and Robertson, 1970
Buku Teks SO