I remember you could buy it as course materials for some The Institutes class, but I don’t remember which one and I’m having trouble finding how to buy the book from the website.
I found this on Reddit from 2 years ago
I’ve reached out the CAS about this and was told that we have to call the Insitutes directly and order the text over the phone. I bought it two days ago after a weeks long search.
I vaguely remember just using the battle acts summary or someone else had the book at work.
Also found these flash cards for exam 6 with a deck for each of the 7 Porter chapters that are tested - Exam 6 - Online Flashcards by Steve Giusti | Brainscape