McCormick, Donald, 1911-, author
Facts on File, 1990
Buku Teks
Brachet, Michelle, author
Murray Books (Australia, 2012
Buku Referensi
Saricks, Joyce G., author
[American Management Association, ], 2009
eBooks
Jacobs, Hayes B., author
Writer`s Digest Books, 1968
Buku Teks
Sharpe, Leslie T., author
Camberidge University Press , 1994
Buku Teks