Corwin, Edward S., author
Great Seal Books, 1955
Buku Teks
Schawartz, Bernard, author
At The University Press, 1955
Buku Teks
Mason, Alpheus Thomas,1899-1989, author
Prentice-Hall, 1993
Buku Teks
Strong, Frank R., author
Dennis & Co., 1950
Buku Teks
Fisher, Louis, author
McGraw-Hill, 1988
Buku Teks