edited by Valerie H. Pitt
Penguin Books, 1991
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Bannock, G., author
Penguin Books, 1974
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Thomas, Merlin, author
Penguin Books, 1985
Buku Referensi
Bannock, G., author
Allen Lane / The Viking Press, 1979
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Bryson, Bill, author
Penguin Books, 1994
Buku Referensi