Adler, Mortimer J., editor in chief
Chicago, Encyclopedia Britanica, Inc, 1990, 1994
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Mortimer J. Adler, editor in chief ; Clifton Fadiman, Philip W. Goetz, associate editors
Encyclopedia Britanica, 1990
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Turner, Ralph, author
McGraw-Hill, 1941
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editor, Robert Maynard Hutchins
Encyclopaedia Britannica, 1952
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Harrison, John B.
Alfred A. Knopf , 1966
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