-[4](https://wiki.haskell.org/Category_theory), where you should follow the further links discussing Functors, Natural Transformations, and Monads.
+[4](https://wiki.haskell.org/Category_theory) <small>(where you should follow the further links discussing Functors, Natural Transformations, and Monads)</small>
+[5](http://www.stephendiehl.com/posts/monads.html)
+