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Dyfyniad Arddull ChicagoCohen, Wesley M., Richard R. Nelson, and John P. Walsh. Protecting Their Intellectual Assets: Appropriability Conditions and Why U.S. Manufacturing Firms Patent(or Not). Cambridge: National Bureau of Economic Research, 2000.
Dyfyniad MLACohen, Wesley M., et al. Protecting Their Intellectual Assets: Appropriability Conditions and Why U.S. Manufacturing Firms Patent(or Not). National Bureau of Economic Research, 2000.
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