diff --git a/doc.html b/doc.html
index b3585783..7af141a1 100644
--- a/doc.html
+++ b/doc.html
@@ -182,7 +182,7 @@
 <map xmlns="http://www.gpxsee.org/map/1.4">
   <name>OSM - HiDPI</name>
   <url>https://a.osm.rrze.fau.de/osmhd/$z/$x/$y.png</url>
-  <tile pixelRatio="2">
+  <tile pixelRatio="2"/>
 </map>
 </pre>