src/Pure/Thy/thy_read.ML

             | escape ("&"::s) = "&" ^ escape s
             | escape (c::s)   = c ^ escape s;
       in case !cur_htmlfile of
              Some out =>
                (mk_theorems_title out;
-                output (out, "<EM>" ^ name ^ "</EM>\n<PRE>" ^
+                output (out, "<DD><EM>" ^ name ^ "</EM>\n<PRE>" ^
                              escape 
 			      (explode 
 			       (string_of_thm (#1 (freeze_thaw thm)))) ^
                              "</PRE><P>\n")
                )