Walz, Jay
Atheneum, 1966
Buku Teks SO
Walker, Allan S.
Australian War Memorial, 1956
Buku Teks SO
Jack M. Sasson, Johan Baines, Gary Beckman, Karen S. Rubinson, editor
Charles Scribner's Sons, 1995
Buku Referensi
edited by Jack M. Sasson
Simon & Schuster, 1995
Buku Teks
Lewis, Bernard
Weidenfeld and Nicolson, 1998
Buku Teks SO