Duncan, Peter
Sage, 2014
Buku Teks SO
edited by Tom Sorell
Routledge, 1998
Buku Teks
Harold W. Baillie, John McGeehan, Thomas M. Garrett, Rosellen M. Garrett
Pearson, 2013
Buku Teks SO
Hall, George M.
Warren H. Green, 1992
Buku Teks SO
Darr, Kurt
The John Hopkins University Press , 1997
Buku Teks