Gerstman, B. Burt
Jones and Barlett Publishers, 2008
Buku Teks
Schork, M. Anthony
Prentice-Hall, 2000
Buku Teks
Finney, D.J.
Chapman & Hall, 1980
Buku Teks
Gerstman, B. Burt
Massachusetts Jones & Bartlett Learning, 2015
Buku Teks
Sokal, Robert R.
W.H. Freeman, 1969
Buku Teks