The Revised Report on Algol 68 came out in 1974,
five years after the
original report
It cleared up a number of problems with the original definition, but by this time other variants had been implemented, notably Algol 68-R at the Royal Radar Establishment (Malvern) for ICL machines.
Nottingham staff were on the BCS Algol committee advising on the changes required to the original report.
This is the language that was generally implemented,
and influenced the design of many later languages.
In particular the IBM proposal for a general purpose (useful for both scientific and commercial applications) language, PL/I, showed several Algol influences, although IBM would deny this. Influence extended to C, and hence to C++ and Java.