diff --git a/index.html b/index.html
index 11741348..56da38ce 100644
--- a/index.html
+++ b/index.html
@@ -493,7 +493,7 @@ <h3>
             </p>
             <aside class="note">
               <p>
-                An explicit direction value such as "[=text-direction/rtl=]" or
+[=text-direction/auto=] means that the directionality of each member is determined by its first strongly directional character (as per the <a data-cite="bidi#P2">Rule P2</a>). An explicit direction value such as "[=text-direction/rtl=]" or
                 "[=text-direction/ltr=]" is preferred to relying on the default of
                 "[=text-direction/auto=]".
               </p>