Color and Light". It's available on Amazon for about $16 and is well worth it. I'm only about 1/2 way thru it, but I'd have to say it's one of the more comprehensive and clear books on the subject that I have come across. It's easy to understand in terms of both words and visuals to help demonstrate concepts of how and why light and color work the way they do.
I'd recommend it for any artist who wants to paint realistically.
Thank you James for sharing your learning and years of experience to help other artist to grow!