Smith, R. B. (Ralph Bernard), 1939-2000., author
Taylor and Francis , 2012
Buku Teks
Tanham, George K., author
Frederick A. Praeger, 1962
Buku Teks
Hammer, Ellen J.
Stanford University Press, 1954
Buku Teks
Xunhasaba, 1972
Buku Teks
Westview Press, 1991
Buku Teks