Young, E.M.
Routledge, 1997
Buku Teks
Prentice Hall Inc., 1969
Buku Teks
Wortman, Sterling
Johns Hopkins University Press, 1979
Buku Teks SO
Garst, Jonathan
Random House, 1963
Buku Teks
by Andrew Schmitz, P. Lynn Kennedy, Troy G. Schmitz
Emerald, 2017
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