diff --git a/doc/gf-history.html b/doc/gf-history.html
index 71306c798..1a6cb98b9 100644
--- a/doc/gf-history.html
+++ b/doc/gf-history.html
@@ -29,8 +29,8 @@ To see the probabilities, use <tt>pg -printer=probs</tt>.
 <br>
 As a by-product, the probabilistic random generation algorithm is
 available for any context-free abstract syntax. Use the flag
-<tt>gr -cf<&tt>. This algorithm is much more efficient than the
-old (more general) one.
+<tt>gr -cf</tt>. This algorithm is much faster than the
+old (more general) one, but it may sometimes loop.
 
 <p>