4Balland P A. Proximity and the evolution of collaboration net- works:evidence from research and development projects within the global navigation satellite system industry[J]. Regional Studies, 2012, 46(6): 741-756.
5Boschma R A. Proximity and innovation: A critical assessment [J]. Regional Studies, 2005, 39(1): 61-74.
6Laura A, Helen S. Geographic proximity and firm-university in- novation linkages:evidence from Great Britain[J]. Journal of Economic Geography, 2011, 11(6): 949-977.
7Eriksson R H. Localized spillovers and knowledge flows:How does proximity influence the performance of plants?[J]. Eco- nomic Geography, 2011, 87(2): 127-152.
8Ponds R, Oort F V, Frenken K. Innovation,spillovers and univer- sity-industry collaboration:an extended knowledge production function approach[J]. Journal of Economic Geography, 2010, 10 (2): 231-255.
9Maggioni M A, Nosvelli M, Uberti T E. Space versus networks in the geography of innovation:A European analysis[J]. Papers in Regional Science, 2007, 86(3): 471-494.
10Ter W J. Boschma R A.applying social network analysis in eco- nomic geography:framing some key analytic issues[J]. The An- nals of Regional Science, 2009, 43(3): 739-756.
