Martin, William J.
Aslib Gower, 1995
Buku Teks
Currie, Wendy
John Wiley & Sons, 2000
Buku Teks
Currie, Wendy
John Wiley & Sons, 2000
Buku Teks
Barber, William J.
Stanford University, 1961
Buku Teks
Gelinas, Ulric J.
PWS-KENT Publishing Company, 1990
Buku Teks