E. Wainright Martin ... [and others]
Pearson, 2002
Buku Teks
Kanter, Jerome
Prentice-Hall, 1992
Buku Teks
Roberts, Sue
Facet Publishing, 2004
Buku Teks
Cricket Liu; Jerry Peek; Russ Jones; Bryan Buus; Adrian Nye
O'Reilly, 1994
Buku Teks
Kanter, Jerome
Englewood Cliffs, N.J. Prentice-Hall 1992,
Buku Referensi