edited by Andrew Heritage
Dorling Kindersley, 2000
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Reader's Digest Association.
Reader's Digest Association, 1968
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C. S. Hammond and Company
C.S. Hammond & Co., [date of publication not identified]
Buku Teks
C.S. Hammond , 1961
Buku Referensi
C.S. Hammond & Co. , 1960
Buku Referensi