[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/>.