Marris, Robin
Free Press of Glencoe, 1964
Buku Teks
Berry, Aidan
Chapman and Hall, 1991
Buku Teks
Hogerth, Robin M.
John Wiley & Sons, 1979
Buku Teks
Mac Stravic, Robin E. Scott
Aspen Systems Corp., 1980
Buku Teks
MacStravic, Robin E. Scott
Aspen Systems Corp., 1977
Buku Teks