diff --git a/12-interfaces.html b/12-interfaces.html
index 314e678..73a2053 100644
--- a/12-interfaces.html
+++ b/12-interfaces.html
@@ -54,7 +54,7 @@ <h3>Putting our Interface to Use</h3>
     <footer>
         <a href="11-newcomp.html">&lt;&lt; 11 - New Components</a>
         <a href="index.html">Back to list</a>
-        <a href="13 - router">13 - Router &gt;&gt; </a>
+        <a href="13-router.html">13 - Router &gt;&gt; </a>
     </footer>
 </body>
-</html>
\ No newline at end of file
+</html>