The New Encyclopaedia Britannica : volume 22, micropaedia konowledge in depth
Encyclopaedia Britannica Inc., 2002
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The New encyclopaedia Britannica : volume 22, macropaedia knowledge in depth
Encyclopaedia Britannica Inc., 1998
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Encyclopaedia Britannica : volume 22
Encyclopaedia Britannica Inc., 1967
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Encyclopaedia Britannica : volume 22
Encyclopaedia Britannica Inc., 1968
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Encyclopaedia universalis : volume 22
Encyclopaedia Universalis France S.A. , 1989
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