Zahn, Markus
Krieger, 1987
Buku Teks
Siegel, Daniel M.
Cambridge University Press, 1991
Buku Teks SO
Paul, Clayton R.
McGraw-Hill, 1982
Buku Teks SO
Eyges, Leonard
Dover Publication. Inc, 2015
Buku Teks SO
Sarwate, V.V.
John Wiley & Sons, 1993
Buku Teks SO