The Encyclopedia Americana : volume 27
Americana Corporation, 1977
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The Encyclopedia Americana : volume 27
Americana Corporation, 1964
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The Encyclopedia Americana : the international reference work, volume 27
Americana Corporation, 1960
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Encyclopaedia universalis : volume 27
Encyclopaedia Universalis France S.A. , 1989
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The New Encyclopaedia Britannica : volume 27
Encyclopaedia Britannica Inc., 1988
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