Update README.md

Author: ggorman

README.md

@@ -4,3 +4,6 @@ Introduction to programming for geoscientists
 This course closely follows the text book ["A Primer on Scientific Programming with Python", by Hans Petter Langtangen](http://www.springer.com/mathematics/computational+science+%26+engineering/book/978-3-642-18365-2).
 
 An updated version of this course can always be found on the [github page](http://ggorman.github.io/Introduction-to-programming-for-geoscientists/)
+
+## License
+All the course material is licensed under a Creative Commons Attribution 3.0 Unported (CC BY 3.0)  (http://creativecommons.org/licenses/by/3.0/) and MIT License - http://opensource.org/licenses/mit-license.html.