This list on the structure of the OACS permissioning system
was provided by <jadeforrest> via the IRC #openacs (thanks):
https://openacs.org/doc/openacs-HEAD/permissions.html, https://openacs.org/doc/openacs-HEAD/permissions-tediously-explained.html
https://openacs.org/doc/openacs-HEAD/permissions-requirements.html
https://openacs.org/doc/openacs-HEAD/permissions-design. html
There is also this forum post by Randy O'Meara on Aug 17 2003 which looks like the latest/most succinct on the subject: https://openacs.org/forums/message-view?message_id=116231
<jadeforrest> also pointed out Joel Aufrecht's "How Do I" section found in Chapter 4 of the Administrator's Guide (Part II of the OpenACS Core Documentation):
https://openacs.org/doc/openacs-HEAD/how-do-I.html
