Johnston, John B.
Addison-Wesley, 1966
Buku Teks SO
Ignizio, James P.
Sage, 1985
Buku Teks SO
Feiring, Bruce R.
Sage University Paper, 1986
Buku Teks SO
Bolton, William, 1933-
Longman Scientific & Technical, 1995
Buku Teks SO
Thie, Paul R.
John Wiley & Sons, 1979
Buku Teks SO