diff --git a/documents/references.md b/documents/references.md
index 46bacf7576e18bc81a07180da202a832aa1b4870..ec2740dad3e3adcdee11bb17ba887cbec8af7d41 100644
--- a/documents/references.md
+++ b/documents/references.md
@@ -26,6 +26,9 @@ Includes anything from stack overflow links to notes about logic from previous w
 ### Character to Int
 <https://stackoverflow.com/a/704160>
 
+### Parse Hex Values
+<https://stackoverflow.com/a/604413>
+
 
 ## Makefile
 * Purpose of ".PHONY" - <https://stackoverflow.com/a/2145605>