Fix tag.

doc/src/sgml/queries.sgml

-<!-- $Header: /cvsroot/pgsql/doc/src/sgml/queries.sgml,v 1.3 2001/02/10 08:30:13 tgl Exp $ -->
+<!-- $Header: /cvsroot/pgsql/doc/src/sgml/queries.sgml,v 1.4 2001/02/13 21:13:11 petere Exp $ -->
 
 <chapter id="queries">
  <title>Queries</title>
@@ -747,7 +747,7 @@ SELECT <replaceable>select_list</replaceable> FROM <replaceable>table_expression
 </synopsis>
    <replaceable>column1</replaceable>, etc., refer to select list
    columns.  These can be either the output name of a column (see
-   linkend="queries-column-labels">) or the number of a column.  Some
+   <xref linkend="queries-column-labels">) or the number of a column.  Some
    examples:
 <programlisting>
 SELECT a, b FROM table1 ORDER BY a;