The encyclopedia of philosophy; volume 7 and 8
editor in chief, Paul Edwards
Macmilan , 1972
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International encyclopedia of the social sciences : volume 7 & 8
edited by David L. Sills
Macmillan and The Free Press, 1968
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The Encyclopedia Americana : volume 8
Americana Corporation, 1977
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The Encyclopedia Americana : volume 8
Americana Corporation, 1964
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Collier's encyclopedia : volume 8
Macmillan Educational Company, 1990
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