Philip's millenium encyclopedia
George Philip Limited, 1999
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Larousse illustrated international encyclopedia
Larousse , 1972
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McWhirter, Norris
Dunlop illustrated encyclopedia of facts / compiled by Norris and Ross McWhirter
Doubleday, 1969
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The encyclopedia American
Americana Corporation, 1980
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The Columbia encyclopedia
Columbia University Press, 1950
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