5Worley J S. Industrial research and the new competition [ J ]. Journal of Political Economy, 1961,3 (2) : 127-- 140.
6Baruch L, Sougiannis T. The capitalization, amortization, and value-relevance of R&D[J ]. Journal of Accounting and Economics, 1996,21 ( 1 ) : 107--138.
7Evnge L, Savona M. Innovation, employment and skills in services: Firm and sectoral evidence [ J ]. Structural Change and Economic Dynamics ,2003 (14) :449-474.
8Lichtenberg F R. R&D investment and international productivity differences [ R]. Cambridge, MA: National Bureau of Economic Research, Working Paper, 1992.4161.
9Barker V L Ⅲ, Muller G C. CEO characteristics and finn R&D spending[J]. Management Science , 2002 , 4$ (6) :782--801.
10Henderson R, Cockburn I. Finn size and research productivity in drug discovery [ A ]. In Jacobzone S (ed). La Sante: Trajectoires D' avenir [ M ]. Paris : INSEE, 1997.