Hare, Van Court
Harcourt, Brace and World, 1967
Buku Teks
Davis, Williams
Addison-Wesley, 1983
Buku Teks
Satzinger, John W.
Course Tecnology Cengage, 2012
Buku Teks
Dennis, Alan, 1951-
Wiley Blackwell, 2015
Buku Teks
McMillan, Claude
R.D. Irwin, 1973
Buku Teks