File(s): File format is text/html https://www.frbsf.org/research-and-insights/publications/economic-letter/2003/09/are-we-running-out-of-new-ideas-a-look-at-patents-and-research-and-development/

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File(s): https://fraser.stlouisfed.org/title/economic-letter-federal-reserve-bank-san-francisco-4960/running-new-ideas-a-look-patents-r-d-633225