diff --git a/doc/user/tasub.htm b/doc/user/tasub.htm
index 130cb29e..03a785c7 100644
--- a/doc/user/tasub.htm
+++ b/doc/user/tasub.htm
@@ -87,6 +87,8 @@ In order to calculate a UB matrix a list of reflections must be maintained. This
   have the correct angular difference to a previous reflection. This is a help 
   for setting up the instrument or running powder mode. When a UB has been 
   generated from auxiliary reflections, a3, sgu and sgl angles will be incorrect. 
+ <dt>tasub repref id qh qk ql a3 a4 sgu sgl ei ef
+ <dd>Modifies the reflection with id id to have the values given. 
  </dl>
 </p>
 <h3>Calculations</h3>