Held, Colbert C.
Westview Press, 2014
Buku Teks
Held, Colbert C., author
Westview Press, 1989
Buku Teks
Palmer, Monte, author
Thomson Wadsworth, 2007
Buku Teks
Bill, James A., author
Littel Brown and Company, 1984
Buku Teks
Bill, James A., author
Little, Brown, 1979
Buku Teks