3Bell D E, Leonard J L. Secure Computer System: Unified Exposition and MULTICS Interpretation[R], Bedford, MA, USA: The Mitre Corporation, Tech. Rep.: MTR-2997, 1976.
4Feiertag R J, Levitt K N, Robinson L. Proving Multilevel Security of a System Design[C]. Proc. of the 6^th ACM Syrup. on Operating Syst.Principles, 1977: 57-65.
5Denning D E. A Lattice Model of Secure information Flow[J].Communications of the ACM, 1976, 19(5): 236-243.
6Bell T Y L, LaPadula A. A "New" Paradigm for an "Old" Model[C].Proceedings of the 1992-1993 Workshop on New Security Paradigms,1993: 82-93.
7Lampson W. A Note on the Confinement Problem[J]. Communications of the ACM, 1973, 16(10): 613-615.
