Routledge, 2004
Buku Teks SO
Gardner, Philip
Routledge, 2010
Buku Teks SO
Malchow, Howard L.
Bloomsbury Academic, an imprint of Bloomsbury Pub, 2016
Buku Teks SO
Elton, Geoffrey Rudolph
Sydney University Press, 1967
Buku Teks SO
Renier, G.J.
Harper and Row, 1965
Buku Teks SO