Shresthova, Sangita, author
Sage, 2011
Buku Teks
Helm, Thomas.
Dodd, Mead, 1960.
Buku Teks
Acuff, Frank L., author
American Management Association, 2008
eBooks
Listri, Massimo, author
Thames & Hudson, 2008
Buku Referensi
McKay, Sandra Lee, author
Routledge, 2016
Buku Teks