1. Brosgol, B.M., Dreisbach, T.A., Felty, J.L., Lexier, J.R., Palter, G.M., CS-4 Language Reference Manual and Operating System Interface, Part I, Intermetrics, Inc., 701 Concord Avenue, Cambridge, Massachusetts 02138, IR# 130-2, October 1975.
2. Dahl, O.J., Myhrhaug, B. and Nygaard, K., SIMULA Common Base Language, Norwegian Computing Center, Norway, 1970.
3. Fischer, A. and Fischer, M., "Mode Modules as Representations of Domains", ACM Symposium on Principles of Programming Languages, Boston, 1973.
4. Hoare, C.A.R., "Data Reliability", in [SIGPLAN 75].
5. IFIP Working Group 2.1 on ALGOL, New Directions in Algorithmic Languages, Institut de Recherche D'Informatique et D'Automatique, France, 1975.