Curry, Dudley W.
Prentice- Hall International , 1972
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Computer Station, 1981
Buku Referensi
Kennedy, David
Bay Books, 1988
Buku Referensi
Bernstein, Lewis
Norwalk Appletton century crofts , 1985
Buku Teks
Parkin, Alan C.
John Wiley & Sons, 1999
Buku Teks SO