Oxley, Harold
Gunung Mulia, 1993
Buku Teks
Lawrence Erlbaum Associates, Publishers, 2003
Buku Teks
Cutlip, Scott M., author
Prentice Hall International, 2000
Buku Teks
Smith, Ronald D., author
Lawrence Erlbraum Associates, Publishers, 2005
Buku Teks
Smith, Ronald D., author
Lawrence Erlbraum Associates, Publishers, 2005
Buku Teks