diff --git a/source b/source
index 7e614ab1e22..275becd3136 100644
--- a/source
+++ b/source
@@ -53714,8 +53714,9 @@ interface <dfn interface>HTMLButtonElement</dfn> : <span>HTMLElement</span> {
   <span>reflect</span> the element's <code data-x="attr-button-commandfor">commandfor</code>
   content attribute.</p>
 
-  <p>The <code data-x="dom-button-command">command</code> IDL attribute must <span>reflect</span>
-  the content attribute of the same name.</p>
+  <p>The <dfn attribute for="HTMLButtonElement"><code
+  data-x="dom-button-command">command</code></dfn> IDL attribute must <span>reflect</span> the content
+  attribute of the same name.</p>
 
   <p>The <dfn attribute for="HTMLButtonElement"><code data-x="dom-button-value">value</code></dfn>
   IDL attribute must <span>reflect</span> the content attribute of the same name.</p>