diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 20da3ed0334..cec21e42c05 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -8748,6 +8748,12 @@ SELECT regexp_match('abc01234xyz', '(?:(.*?)(\d+)(.*)){1,1}');
to_char(current_timestamp, 'FMDay, FMDD HH12:MI:SS')
'Tuesday, 6 05:39:18'
+
+ to_char(current_timestamp AT TIME ZONE
+ 'UTC', 'YYYY-MM-DD"T"HH24:MI:SS"Z"')
+ '2022-12-06T05:39:18Z',
+ ISO 8601 extended format
+
to_char(-0.1, '99.99')
' -.10'