Wilson, Bright E., Jr.
Dover Publications, 1990
Buku Teks
Freedman, Paul, author
Public Affairs Press, 1950
Buku Teks
Hillway, Tyrus, author
Houghton Miffiln, 1964
Buku Teks
Wilson, E. Bright, author
McGraw-Hill, 1952
Buku Teks
Haring, Lloyd
Wm. C. Brown Co. Pub., 1983
Buku Teks