Freedman, M. David
John Wiley & Sons, 1972
Buku Teks SO
Fishman, George S.
Wiley, 1978
Buku Teks SO
Murray, William D.
Prentice-Hall, 1990
Buku Teks SO
Springer International Publishing, 2016
eBooks
Ercegovac, Milos D.
John Wiley & Sons, 1985
Buku Teks SO