Conger, Joan E., author
Libraries Unlimited, 2004
Buku Teks
Kohn, Karen C., 1978, author
Rowman & Littlefield, 2015
Buku Teks
Pitman, Lesley, author
Elsevier, 2015
Buku Teks
Jordan, Peter, author
Gower, 1998
Buku Teks
Mavodza, Judith, author
Chandos Publishing, 2016
Buku Teks