Reddit mentions of Play Your Best Pool

Way overrated imo.

Awkward diagrams, and the author gives some questionable advice (particularly about rail cut shots).

99CS is definitely worth a read, but Play Your Best Pool, Byrne's Standard, A Smarter Way to Learn Pool, and Dr. Dave's Illustrated Principles are all better options imho.

I would recommend you to watch people play snooker/9 ball/8 ball to get a very good knowledge on billiards. Also, look at snooker player's stance to get a sense of what a proper form looks like.

For books, I recommend The Illustrated Principles of Pool and Billiards and Play Your Best Pool. These books will give you the best knowledge on how and why things happen in billiards, such as the spin both balls receive after contact. They also give you the thought process behind pros so you'll gain a lot by supplementing these books with watching professionals. If you're looking for a practice book, Practicing Pool can provide a simple set up of practice. I was a bit disappointed by the book but it can definitely show you how to start practicing.