Thompson, Warren S., author
The University of Chicago Press, 1959
Buku Teks
Peterson, A.D.C., author
Gerald Duckworth, 1949
Buku Teks
Hyma, Albert, author
George Wahr, 1953
Buku Teks
Peffer, Nathaniel, author
University of Michigan Press, 1958
Buku Teks
Quigley, Harold S., author
World Peace Foundation, 1938
Buku Teks