6Adams, J.D. and Jaffe, A. B, 1996, "Bounding the Effects of R&D: An Investigation Using Matched Establishment-Firm Data", Round Journal of Economics, 27(4), 700-721.
7Bemstein, J.I, 1988, "Costs of Production, Intra- and Inter-Industry R&D Spillovers: The Canadian Evidence", Canadian Journal of Economics, 21(2), 324-347.
8Bound, S. Harhoff, D. and Van Reenen, J, 2002, "Corporate R&D and Productivity in Germany and the United Kingdom", Working Paper.
9Congeress of the United States, Congressional Budget Office, 2005, "R&D and Productivity Growth", http://www. cbo. gov/ftpdocs/64xx/doc6482/06 - 17 - R - D. pdf
10Cuneo, P. and Mairesse, J, 1984, "Productivity and R&D at the Firm Level in French Manufacturing", in Griliches, Z. ( ed), R&D, Patents and Productivity, Chicago: University of Chicago Press, 375-392.