Harhoff, Dietmar; Narin, Francis; Scherer, F. M.; … - In: The Review of Economics and Statistics 81 (1999) 3, pp. 511-515
Through a survey, private economic value estimates were obtained on 964 inventions made in the United States and Germany and on which German patent renewal fees were paid to full-term expiration in 1995. A search of subsequent U.S. and German patents yielded counts of citations to those patents....