diff --git a/reference/gmp/functions/gmp-fact.xml b/reference/gmp/functions/gmp-fact.xml
index 0e13336165..dc58908b1d 100644
--- a/reference/gmp/functions/gmp-fact.xml
+++ b/reference/gmp/functions/gmp-fact.xml
@@ -13,7 +13,7 @@
    <methodparam><type class="union"><type>GMP</type><type>int</type><type>string</type></type><parameter>num</parameter></methodparam>
   </methodsynopsis>
   <para>
-   Calculates factorial (<literal>a!</literal>) of <parameter>num</parameter>.
+   Calculates factorial (<literal>num!</literal>) of <parameter>num</parameter>.
   </para>
  </refsect1>