Zofi, Yael, author
Amacom, 2012
Buku Teks
Rullo, Thomas A., author
PBI, 1977
Buku Referensi
Kepner, Charles Higgins, 1922-, author
Princeton Research Press, 1981
Buku Teks
Blanchard, Kenneth H., author
Fontana/Collins , 1987
Buku Teks
Blanchard, Kenneth H., author
Fontana/Collins, 1989
Buku Teks