1[3]F.G.Crane.Insurance Principles and Practices[Z].New York:Willey.1984
2[4]C.A.Williams,R.M.Heine.Risk Management and Insurance[Z].New York:McGraw Hill.1985.
3[5]D.Hillson.What is risk Towards a common definition[J].infoRM,2001,(6):16～17.
4[6]S.D.Eskesen,P.R.Tengborg,J.Kampmann,T.H.Veicherts.Guidelines for tunnelling risk management:International Tunneling Association,Working Group No.2[J].Tunneling and Underground Space technology,2004,(19):217～237.
