Barnes, P. W. Economic perspectives on innovation and invention.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रBarnes, Patrick W. Economic Perspectives on Innovation and Invention.
एमएलए (8वां संस्करण) प्रशस्ति पत्रBarnes, Patrick W. Economic Perspectives on Innovation and Invention.
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