Lawson, Joseph W.R., II, author
American Management Association, 1998
eBooks
Waller, Jenny, author
Pustaka Binaman Pressindo, 1994
Buku Referensi
Lawson II, Joseph W. R., author
American Management Association;;, 1998
eBooks
Carpendale, Jeremy, author
Blackwell Publishing, 2006
Buku Teks
Thompson, Frank J., author
Thomson - Wadsworth, 2003
Buku Teks