diff --git a/part-2-reverse-engineering-source-code-of-the-biontech-pfizer-vaccine.md b/part-2-reverse-engineering-source-code-of-the-biontech-pfizer-vaccine.md
index dae18e1..d1391f7 100644
--- a/part-2-reverse-engineering-source-code-of-the-biontech-pfizer-vaccine.md
+++ b/part-2-reverse-engineering-source-code-of-the-biontech-pfizer-vaccine.md
@@ -220,7 +220,7 @@ A sample algorithm
 ------------------
 On the [GitHub repository](https://github.com/berthubert/bnt162b2) you can
 find
-[3rd-gc.gp](https://github.com/berthubert/bnt162b2/blob/master/3rd-gc.go). 
+[3rd-gc.go](https://github.com/berthubert/bnt162b2/blob/master/3rd-gc.go). 
 
 This implements a simple strategy that works like this: