Carlaw, Peggy, author
McGraw-Hill, 1997
Buku Teks
Caroselli, Marlene
McGraw-HIll, 2002
Buku Teks
Newstrom, John W., author
McGraw-Hill, 1997
Buku Teks
Gherardi, Silvia, author
Blackwell Publhiser, 2006
Buku Teks
Ashton, David N., author
International Labour Office, 2002
Buku Teks