Fessenden, Ralph J., author
Wilard Grant Press, 1979
Buku Teks
Baker, A. David, author
West Publishing, 1992
Buku Teks
McMurry, John, author
Brooks/Cole, 2007
Buku Teks
English, James, author
McGraw-Hill, 1956
Buku Teks
Griffin, Rodger W., author
McGraw-Hill, 1969
Buku Teks