Ahituv, Niv
Brown Publisher , 1990
Buku Teks SO
Scott, George M.
RajaGrafindo Persada, 1995
Buku Teks SO
Dickson, Gary W.
McGraw-Hill, 1985
Buku Teks SO
Dickson, Gary W.
McGraw-Hill, 1985
Buku Teks SO
Stair, Ralph M., Jr.
Boyd & Fraser Publishing, 1992
Buku Teks SO