Campbell, Hugh G., author
Prentice-Hall, 1977
Buku Teks SO
Johnston, John B.
Addison-Wesley, 1966
Buku Teks SO
Ignizio, James P., author
Sage, 1985
Buku Teks
Feiring, Bruce R., author
Sage University Paper, 1986
Buku Teks
Bolton, William, 1933-, author
Longman Scientific & Technical, 1995
Buku Teks