Chesters, Sarah Davey
Sense, 2012
eBooks
Gonzales, Joseph
Strategic Information and Research Development Centre, 2011
Buku Teks
Stigum, Marcia
Illinois Dow Jones- Irwin , 1983
Buku Teks
Ellis, Mary
John Murray, 1982
Buku Teks
Atwood, Margaret
Simon and Schuster, 1982
Buku Teks