Hastings House , 1953
Buku Teks SO
Zukav, Gary
William Morrow and Co., 1979
Buku Teks
Donnelly, Thomas C.
The University of Mexico Press, 1953
Buku Teks
Aberle, S. D.
American Anthropological Association, 1948
Buku Teks
Gonzales, Joseph
Strategic Information and Research Development Centre, 2011
Buku Teks