Voigt, Cynthia
Aladdin Paperbacks, 1987
Buku Teks
Stryker, Perrin, author
Harper & Row, 1960
Buku Teks
Norris, Pippa, author
Cornell Selects, an imprint of Cornell University Press, 2017
Buku Teks
Swamy, Narayan, author
Vijitha Yapa Publications, 2006
Buku Teks
Gurian, Michael, author
Jossey-Bass, 2009
Buku Teks