1. T. Anderson (1975). Provably Safe Programs. Tech. Report 70, Computing Laboratory, University of Newcastle upon Tyne.
2. B. L. Clark and F. J. B. Ham (1974). The Project Sue System Language Reference Manual. Tech. Report CSRG-42, Computer Systems Research Group, University of Toronto.
3. J. J. Horning, H. C. Lauer, P. M. Melliar-Smith and B. Randell (1974). A Program Structure for Error Detection and Recovery. Lecture Notes in Computer Science 16, Springer Verlag, pp. 177–193. (Also Chap. 2)
4. B. Randell (1975). System Structure for Software Fault Tolerance. IEEE Trans, on Software Engineering, 1, 2, pp. 220–232. (Also Chap. 1)
5. R. M. Simpson (1974). A Study in the Design of High Integrity Systems. Tech. Report 67, Computing Laboratory, University of Newcastle upon Tyne.