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In addition to Thirteen-Star Flags , Cooper also authored the 1968 work The Invention of the Sewing Machine , which was revised and expanded as The Sewing Machine : Its Invention and Development in 1976 .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
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