4Stiglitz, J., Weiss, A., 1981: Credit Rationing with imperfect Information. America Economic Review 71, No. 3:393 -410.
5Bester, Helmut, 1985, Screening vs. Rationing in credit markets with imperfect information, the American Economic Review 75 (4).
6Berger, A. N and Udell G.. F, Small business credit availability and relationship lending: the importance of banking organization structure, Economical Journal 112(477),32 -54/2002.
6Mcgill M D.Economic and Financial Implications of theAging Phenomenon [J]. Proceedings of the AmericanPhilosophical Society,1998(2) : 154-171.
7Gustafson P.Transnationalism in retirement migration : thecase of North European retirees in Spain [J].Ethnic andRacial Studies,2008(3) :451-475.
8Elisa Alen Nieves Losada.The Impact of Ageing on theTourism Industry : An Approach to the Senior TouristProfile[J].Social Indicators Research,2016( 1 ) : 303-322.
9Leibowitz M L , Bova A , Hammond P. Brett. The EndowmentModel of Investing : Return, Risk and Diversification[M]. Hoboken: John Wiley & Sons,2010.
10Griliches Z.Patents : Recent Trends and Puzzles [C]//Baily M N , Clifford W.Brookings Papers on EconomicActivity,Microeconomics. Washington D.C.:The BrookingsInstitution 1989: 291-319.