8S N Dorogovtesev,J F F. Mendes, evolution of networks[M]. Oxford University Press, Oxford, 2003.
9Uzzi, Brian, Jarrett Spiro. Collaboration and creativity: The small world problem[J]. American Journal of Sociology, 2005,111 : 447- 504.
10Kogut, Bruce, Pietro Urso, Gordon Walker. The emergent properties of a new financial market: American venture capital syndication from 1960 to 2000[J]. Management Science,2007,53.. 1181-1198.