4Berger, A. N. and Udell, G.F. : Small Business Credit Availability and Relationship Lending: The Importance of Bank Organizational Structure[J].Economic Journal, Vol. 112: 32-54, 2002.
5Brugger E. and Rajapatirana S. : New Perspectives On Financing Small Business in Developing Countries[ M]. ICS Press, 1995.
6Stiglitz J. and A. Weiss: Credit rationing in markets with imperfect information[J]. America Economic Review, Vol. 71:393-410, 1981.