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Measuring national technological performance with patent claims data

Xuesong Tong, J.Davidson Frame [url=http://www.sciencedirect.com/science/article/pii/0048733394900507#COR1]
Research Policy
Volume 23, Issue 2, March 1994, Pages 133-141

http://www.sciencedirect.com/science/article/pii/0048733394900507
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