Gaya APA
Fifield, R, H., Pearcy, G, E. (1944).
Geopolitics in Principle and Practice (1).
Boston, USA:
Ginn and Company.
Gaya MLA
Fifield, Russel, H.., Pearcy, G., Etzel.
"Geopolitics in Principle and Practice".
1
Boston, USA:
Ginn and Company,
1944.
Koleksi Elektronik.