diff --git a/doc/src/sgml/datatype.sgml b/doc/src/sgml/datatype.sgml
index c2e42f31c0..0b33d32a1b 100644
--- a/doc/src/sgml/datatype.sgml
+++ b/doc/src/sgml/datatype.sgml
@@ -2766,7 +2766,9 @@ SELECT EXTRACT(days from '80 hours'::interval);
          0
 </programlisting>
 
-     Functions <function>justify_days</function> and
+     Functions <xref linkend="function-justify-days"/> and
+     Functions <link linkend="function-justify-days">justify_days</link> and
+     Functions <link linkend="function-justify-days"><function>justify_days</function></link> and
      <function>justify_hours</function> are available for adjusting days
      and hours that overflow their normal ranges.
     </para>
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 12d75b476f..fd8ba334f8 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -7079,7 +7079,7 @@ SELECT regexp_match('abc01234xyz', '(?:(.*?)(\d+)(.*)){1,1}');
 
        <row>
         <entry>
-         <indexterm>
+         <indexterm id="function-justify-days">
           <primary>justify_days</primary>
          </indexterm>
          <literal><function>justify_days(<type>interval</type>)</function></literal>