Added Books: Grokking Simplicity

readme.md

@@ -58,6 +58,7 @@ a theorem prover called JBob for writing proofs in LISP.
 - [How to Design Programs](http://www.htdp.org/) / [Second Edition](http://www.ccs.neu.edu/home/matthias/HtDP2e/)
 - [Introduction to Functional Programming](http://www.amazon.com/Introduction-Functional-Programming-International-Computing/dp/0134841891)
 - [Haskell in Depth](https://www.manning.com/books/haskell-in-depth) - the perfect second book on Haskell which dives into examples and application scenarios designed to teach how Haskell works and how to apply it correctly. 
+- [Grokking Simplicity: Taming complex software with functional thinking](https://www.manning.com/books/grokking-simplicity) - Teaches functional programming from first principles using real-world scenarios.
 ### Communities
 - [Lambda the Ultimate](http://lambda-the-ultimate.org/) - Community focused on discussing researches, papers
 and hot topic on academia. Very high tech discussion level.