diff --git a/Requirements.md b/Requirements.md
index 1f186a3..334f50d 100644
--- a/Requirements.md
+++ b/Requirements.md
@@ -8,3 +8,4 @@
 * curl : http://curl.haxx.se/
 * EMSL_Basis_Set_Exchange_Local : https://github.com/TApplencourt/EMSL_Basis_Set_Exchange_Local
 * Zlib : http://zlib.net
+* GNU Patch : http://savannah.gnu.org/projects/patch/