diff --git a/content/about.md b/content/about.md
index 3f18404..f91c1fd 100644
--- a/content/about.md
+++ b/content/about.md
@@ -46,7 +46,7 @@ differential privacy to optimization, machine learning, and mechanism design.
 
 ## Teaching ##
 - **Topics in Security and Privacy Technologies (CS 839)**: [F18](https://pages.cs.wisc.edu/~justhsu/teaching/current/cs839/)
-- **Introduction to the Theory and Design of PL (CS 538)**: [S19]((https://pages.cs.wisc.edu/~justhsu/teaching/current/cs538/)
+- **Introduction to the Theory and Design of PL (CS 538)**: [S19](https://pages.cs.wisc.edu/~justhsu/teaching/current/cs538/)
 
 ## Service ##
 - **2019** POPL, PLMW, POST, CSF, DARS (co-chair)