2Ernie Goss, George S Vozikis. High tech manufacturing: Firm size, industry and population density [ J]. Small Business Eco- nomics, 2005 ( 2 ) : 291-297.
3De Jong J, Freel M. Absorptive capacity and the reach of collabo- ration in high-technology small firms[ J]. Research Policy,2010 ( 39 ) :47-54.