1Oakey R P, Cooper S Y. High technology, agglomerationand the potential peripherally sited small firms [J]. Regional Studies, 1989,23(4) :347 - 360.
2Jaffe A, Trajtenberg M, Henderson R. Geographic location of knowledge spillovers as evidenced by patent citations[J]. Quarterly Journal of Economics, 1993,108(3),577 - 598.
3Baptista R, Swanm P. Do firms in clusters innovatemore? [ J ]. Research Policy, 1998,27 (5) : 525 - 540.