Reference [1] in my previous message should have been: https://doi.org/10.1145/365696.365702

> [1] http://doi.acm.org/10.1145/365696.3657022 <http://doi.acm.org/10.1145/365696.3657022>
> [2] http://doi.acm.org/10.1145/2786.2789 <http://doi.acm.org/10.1145/2786.2789>
> [3] http://www.softwarepreservation.org/projects/ALGOL/standards/ <http://www.softwarepreservation.org/projects/ALGOL/standards/>.