Smashing Book 6: New Frontiers in Web Design
These are subjects I'm very passionate about, as accessible web applications are often critically lacking accessibility to a point where they cannot be used by people with disabilities. We can do so much better. I sincerely believe that with more information, developers can make a huge impact in our users' lives.
I also wrote about this subject for Smashing Magazine a few years back, when I was working on the Angular team. The framework code might be a little dated, but the concepts still apply: https://www.smashingmagazine.com/2015/05/client-rendered-accessibility/
You can purchase a hardcover copy from Smashing for $39 US, or $19 US for a digital copy. Do yourself a favor and pick up a copy today! https://www.smashingmagazine.com/2018/09/smashing-book-6-release/