diff --git a/SC3003.md b/SC3003.md
index 88f36d5..79c0602 100644
--- a/SC3003.md
+++ b/SC3003.md
@@ -1,4 +1,4 @@
-## In POSIX sh, $'..' is undefined.
+## In POSIX sh, `$'..'` is undefined.
 
 ### Problematic code: