Aguirre, Adalberto
McGraw-Hill, 2001
Buku Teks SO
Simpson, George Eaton, 1904-
Harper & Brothers, 1958
Buku Teks SO
Hill, Lance
University of North Carolina Press, 2004
Buku Teks SO
edited by Warren G. Bennis, Edgar H. Schei, and David E. Berlew
Dorsey Press, 1964
Buku Teks SO
Padelford, Norman J.
Macmillan, 1962
Buku Teks SO