Turville-Petre, Thorlac
Blackwell Publishing, 2007
Buku Teks
Otis, William Bradley
Barnes & Noble, 1939
Koleksi Publik
Needleman, Morris H.
Barnes & Noble, 1939
Koleksi Publik
Collier, WIlliam Francis
Thomas Nelson and Son, 1920
Buku Teks
Watt, Homer A.
Barnes & Noble, 1957
Buku Referensi