Encyclopaedia Britannica, 1981
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Encyclopaedia Britannica, 1981
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Encyclopaedia Britannica, 1981
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editor, Philip Babcock Gove
Merriam-Webster, 1993
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William Allan Neilson, editor in chief; Thomas A. Knott, general editor; Paul W. Carhart, managing editor
Springfield, G & C Merriam Co.
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