Bourne, S.R. et al "The Design of the Cambridge Algebra System"

[SYMSAM 71] (1971) [ACM] Proceedings of the Second Symposium on Symbolic and Algebraic Manipulation, March 23-25, 1971 Los Angeles (SYMSAM 71)  

Languages mentioned CAMAL {1968} CAMbridge ALgebra system PSYCO {1966} Princeton SYntax COmpiler