Lascarides, Michael
Facet, 2012
Buku Teks SO
American Library Association, 2018
Majalah, Jurnal, Buletin
edited by Samantha Schmehl Hines, Kathryn Moore Crowe
Emerald, 2017
eBooks
Shaffer, Kenneth R.
Scarecrow Press, 1972
Buku Teks SO
edited by Kylie Bailin, Benjamin Jahre, Sarah Morris
Chandos Publishing, 2018
Buku Teks SO