diff --git a/readalongs/static/read-along-1.1.dtd b/readalongs/static/read-along-1.1.dtd
index 8202e169..e862c3e6 100644
--- a/readalongs/static/read-along-1.1.dtd
+++ b/readalongs/static/read-along-1.1.dtd
@@ -100,4 +100,5 @@
 
  <!ELEMENT meta EMPTY>
  <!ATTLIST meta name CDATA #REQUIRED
-   content CDATA #REQUIRED>
+   content CDATA #REQUIRED
+   id CDATA #IMPLIED>