Gilbert, Philip & William G. Mclellan "Compiler generation using formal specification of procedure-oriented and machine languages"

[AFIPS] Proceedings of the 1967 Spring Joint Compu (1967) [AFIPS] Proceedings of the 1967 Spring Joint Computer Conference, April 18-20, Atlantic City, N. J. SJCC 30  

Languages mentioned BASE {1967} Intermediate language for multiple-language compiler