4Berger P,Ofek E.Diversification's Effect on Firm Value[J].Journal of Financial Economics,1995 (37):39 -65.
5Martin D,Sayrak A.Corporate Diversification and Shareholder Value:A Survey of Recent Literature[J].Journal of Corporate Finance,2003(9):37-57.
6Berle A,Means G.The Modern Corporation and Private Property[M].MacMillan,New York,N Y,1932.
7Jensen M,Meckling W.Theory of the Firm:Managerial Behavior,Agency Costs and Ownership Structure[J].Journal of Financial Economics,1976 (3):60-305.
8Jensen M.Agency Costs of Free Cash Flow,Corporate 58Finance and Takeovers[J].American Economic Review,1986,76(1):323 -329.
9Shleifer A,Robert V.Managerial Entrenchment-the Case of Manager Specific Investments[J].Journal of Financial Economics,1989 (25):123-139.
10Gibbons R,Kevin J.Optimal Incentive Contracts in the Presence of Career Concerns:Theory and Evidence[J].Journal of Political Economy,1992,100 (3):468-505.
