by Timothy W. Koch [and others]
Cengage Learning Asia, 2014
Buku Teks
Thomas N. Ingram...[et al.]
Harcourt College Publishers, 2001
Buku Teks
Mathur, Kamlesh
Prentice-Hall, 1994
Buku Teks
Herrmann, Jeffrey W.
Wiley, 2015
Buku Teks
Carnegie, Dale, 1888-1955
Dale Carnegie & Associates, 1984
Buku Teks