Lewis, Bermnard
University of Chicago Press, 1988
Buku Teks
New York : Cambridge University Press
Majalah, Jurnal, Buletin
Malmstrom, Jean
Hayden Book Company, 1965
Buku Teks
Bram, Joseph
Random House, 1955
Buku Teks
Downes, William
Cambridge University Press, 2003
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