Update README.md

Author: thomasnield

README.md

@@ -14,9 +14,9 @@ RxJavaFX is a lightweight library to convert JavaFX events into [RxJava](https:/
 
 ## Documentation
 
-[Learning RxJava with JavaFX (EAP)](https://www.gitbook.com/book/thomasnield/rxjavafx-guide/details)
+[Learning RxJava with JavaFX (EAP)](https://www.gitbook.com/book/thomasnield/rxjavafx-guide/details) - free eBook teaching RxJava 1.0 from a JavaFX perspective.
 
-[Learning RxJava](https://www.packtpub.com/application-development/learning-rxjava)
+[Learning RxJava](https://www.packtpub.com/application-development/learning-rxjava) - Packt book that teaches RxJava 2.0 in depth, with a few RxJavaFX examples.
 
 [![](https://dz13w8afd47il.cloudfront.net/sites/default/files/imagecache/ppv4_main_book_cover/9781787120426.jpg)](https://www.packtpub.com/application-development/learning-rxjava)