diff --git a/README.md b/README.md
index 2a62459..cab7250 100644
--- a/README.md
+++ b/README.md
@@ -26,7 +26,7 @@ These projects are mostly done
 - We construct the Atiyah-Hirzebruch and Serre spectral sequences for cohomology.
 
 ### Future directions
-- Hurewicz Theorem and Hurewicz theorem modulo a Serre class.
+- Hurewicz Theorem and Hurewicz theorem modulo a Serre class. There is a proof in Hatcher. Also, [this](http://www.math.uni-frankfurt.de/~johannso/SkriptAll/SkriptTopAlg/SkriptTopCW/homotop12.pdf) might be useful.
 - Homological Serre spectral sequence.
 - Interaction between steenrod squares and cup product with spectral sequences
 - ...
@@ -98,4 +98,4 @@ These projects are mostly done
 - We will try to make sure that this repository compiles with the newest version of Lean 2.
 - Installation instructions for Lean 2 can be found [here](https://github.com/leanprover/lean2).
 - Some notes on the Emacs mode can be found [here](https://github.com/leanprover/lean2/blob/master/src/emacs/README.md) (for example if some unicode characters don't show up, or increase the spacing between lines by a lot).
-- If you contribute, please use rebase instead off merge (e.g. `git pull -r`).
\ No newline at end of file
+- If you contribute, please use rebase instead off merge (e.g. `git pull -r`).