Bowlden, H.J. "An introduction to Algol 68"
(1978)
[HOPL I] (1979)
SIGPLAN Notices 14(04) April 1979 including The first ACM SIGPLAN conference on History of programming languages (HOPL) Los Angeles, CA, June 1-3, 1978
Languages mentioned
ALGOL 68
{1968} 3rd generation ALGOL