Evans, B. Ifor
Penguin Books , 1948
Buku Teks
Collier, WIlliam Francis, author
Thomas Nelson and Son, 1920
Buku Teks
Wyld, H.C.
Oxford Blackwell 1953
Buku Teks
Fennell, Barbara A., author
Blackwell Publishers, 2001
Buku Teks
Blamires, Harry, author
Longman, 1989
Buku Teks