[Cohen85-2] F. Cohen A Secure Computer Network Design, IFIP, TC-11 Computers and Security, V4#3, Sept. 1985, pp 189-205, also appearing in AFCEA Symp. and Expo. on Physical and Electronic Security, Aug. 1985. [This paper describes the combination of the Bell-LaPadula and Biba models, extends previous results to computer networks, and introduces some major insecurities in computer networks.]