Chabot, Christian N.
McGraw-Hill , 1999
Buku Teks SO
Sengupta, Jayshree
Academic Foundation, 2007
Buku Teks SO
Nicoll, William
Harvester Wheatsheaf, 1994
Buku Teks SO
Mears, Leon A.
GadjahMada University Press, 1981
Buku Teks
Cleaver, Tony
Routledge, 1997
Buku Teks SO