Fulk, R. D. (Robert Dennis), author
Wiley-Blackwell, 2013
Buku Teks
Otis, William Bradley, author
Barnes & Noble, 1939
Koleksi Publik
Collier, WIlliam Francis, author
Thomas Nelson and Son, 1920
Buku Teks
Blamires, Harry, author
Longman, 1989
Buku Teks
Evans, B. Ifor
Penguin Books, 1944
Buku Teks