Unrau, Harlan D.
National Park Service, 1976
Buku Teks
Watson, Adam, author
Routledge , 1997
Buku Teks
Salisbury, Harrison E.
Harrison, 1969
Buku Teks
Clausewitz, Carl von, author
A Millennium Project, 1993
Buku Referensi
Singh, Bilveer, 1956-, author
Greenwood Press, 2002
Buku Teks