Andres, Cameron K.
Prentice-Hall, 2001
Buku Teks SO
Smith, Ronald C.
Prentice-Hall, 1993
Buku Teks SO
Fatzinger, James A. S.
Pearson-Prentice Hall, 2004
Buku Teks SO
Liebing, Ralph W.
John Wiley & Sons, 1982
Buku Teks SO
Emmitt, stephen
Wiley-Blackwell, 2010
Buku Teks SO