Crocker, Mary E. Coffman, author
McGraw-Hill, 1990
Buku Teks
Graham, Gaelle, author
Kesaint Blanc, 2011
Buku Teks
Bishop, Graham, author
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Buku Teks
Moffatt, C.W. Paget
University Tutorial Press, 1`929
Buku Teks
Mont, Francis M Du
Barnes & Noble , 1947
Buku Teks