Here are three additional references on applied Just Intonation.

The first book is abstracted away from composition and provides a more general description of tuning systems.

The next two are composition focused, explaining how tuning system is an option for musical works.

1) The book "How Equal Temperament Ruined Harmony" provides excellent historical context on why ET was a great solution and how we kind of got stuck with it.

While it could be read by anybody, having a bit of musical knowledge OR physics of acoustics knowledge may benefit you.

https://www.amazon.com/Equal-Temperament-Ruined-Harmony-Shou...

There are also two composers who recognize ET as a constraint (as opposed to the "the only option").

2) Harry Partch built many of his own instruments to circumvent issues from 12ET and composed music just for them. He describes his conceptualizations of JI in "Genesis Of A Music":

https://www.amazon.com/Genesis-Music-Account-Creative-Fulfil...

3) Paul Hindemtith also has some opinions on the matter, though both Partch and I disagree with his points of view. Nonetheless he has some at-the-time innovating ideas, some of which are valid and others of which may not have aged well. You can read about them in "The Craft of Musical Composition"

https://www.amazon.com/Craft-Musical-Composition-Theoretical...

You might find this book interesting:

http://www.amazon.com/Equal-Temperament-Ruined-Harmony-Shoul...

Conversationally written and accurate (so far as I was able to tell, I only had time to read a few chapters)