Added resources for learning Forth

Author: nomennescio

README.md

@@ -1,11 +1,19 @@
 ## ttester Codewars
 
-`ttester.fs` extension to output test results for Codewars.
+`ttester.fs` extension to output Forth test results for Codewars.
 
 This project is work in progress.
 
 Please contribute to improve Forth support on Codewars.
 
+## Learning Forth
+
+Some excellent sources to get you started learning Forth:
+
+* [Learn Forth in x minutes](https://learnxinyminutes.com/docs/forth/)
+* [Starting Forth](https://www.forth.com/starting-forth/0-starting-forth/)
+* [Thinking in Forth](http://thinking-forth.sourceforge.net/)
+
 ## Example
 
 See [example](./example).