Reddit mentions: The best tennis books

Awesome! By honing your game and playing matches, you will build up your "tournament toughness" and be less nervous during critical points. Highly recommend this quick read: Tournament Tough! A Guide To Playing Championship Tennis https://www.amazon.com/dp/B00CCSKTQ8/ref=cm_sw_r_cp_api_m13PybD2PFP52

It's a bit dated, but I feel the content is still relevant and will help you most when your strokes are reliable. Good luck and kick some butt!

Get the book "Technical Tennis" by Cross and Lindsey. Chapter 4: Spin and Trajectory.

Also, as some one said, Magnus effect:
https://en.wikipedia.org/wiki/Magnus_effect

When thinking of spin I think it helps to breakdown spin into rotations around 3 fundamental axes: X, Y, and Z axis of the ball, with rotation around X axis for topspin (and backspin), Y axis for sidespin, and the Z axis. Any spin can therefore be thought of as the combination of spins around these three axes. For example, a ball with some topspin and some side spin can thought to be spinning around both the X and Y axes, which can then tell us how the ball with behave when traveling through the air, in this case, arcing downward and to the side.

It might be worth pointing out that Z axis spin (also called spiral spin) has no effect on the flight of the ball but can have a huge effect in the reaction of the ball off the court.

"Tennis ProGuide: A Tennis Guidebook - For those who want to become professional step by step"

http://www.amazon.com/Tennis-ProGuide-Guidebook-become-professional/dp/1494279584/

Someone said this is a good book: http://www.amazon.com/Vic-Bradens-Mental-Tennis-Yourself/dp/B0046LUHXO

Hey now! We had a black tennis pro at our club once.

And he wrote a book about it https://www.amazon.com/Didnt-Know-Was-Black-Growing/dp/145632215X

which was a very disappointing read.