edited by Michael Pacione
Barnes & Noble Books, 1983;1983;1983;1983;1983;1983
Buku Teks SO
Chitambar, J.B.
Wiley Eastern Limited, 1973
Buku Teks SO
Nasional Geographic, 2009
Buku Teks SO
edited by Michael Pacione
Routledge, 2014
Buku Teks SO
Woods, Michael
Sage, 2012
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