Artikel Jurnal
Elliot, H.M., Sir, author
Susil Gupta, 1953
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Read, H.H., author
ELBS and Macmillan, 1975
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Editor: A.J. Stockwell, R. Asthon
HMSO, 1995
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Sears, Francis W. (Francis Weston), 1898-1975, author
Addison-Wesley , 1982
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