Palmer, Alan, author
Routledge, 1996
Buku Referensi
editor, Robert Aldrich, Garry Wotherspoon.
Roudledge, 2001
Buku Referensi
Keegan, John, author
Routledge, 1996
Buku Referensi
Keegan, John, author
Routledge, 1996
Buku Referensi
Hazel, John, author
Routledge, 2000
Buku Teks