edited by, Elise C. Smith and Louise Fiber Luce
Nuwbury House Publishers, 1979
Buku Teks SO
H'raf Press, 1967
Buku Teks
Singh, N.K.
Springer, 2012
eBooks
Sage, 2018
Majalah, Jurnal, Buletin
edited by Caroline B. Brettell and Carolyn F. Sargent
Routledge, 2017
Buku Teks SO