+@node Combined date and time of day items
+@section Combined date and time of day items
+
+@cindex combined date and time of day item
+@cindex ISO 8601 date and time of day format
+@cindex date and time of day format, ISO 8601
+
+The ISO 8601 date and time of day extended format consists of an ISO
+8601 date, a @samp{T} character separator, and an ISO 8601 time of
+day. This format is also recognized if the @samp{T} is replaced by a
+space.
+
+In this format, the time of day should use 24-hour notation.
+Fractional seconds are allowed, with either comma or period preceding
+the fraction. ISO 8601 fractional minutes and hours are not
+supported. Typically, hosts support nanosecond timestamp resolution;
+excess precision is silently discarded.
+
+Here are some examples:
+
+@example
+2012-09-24T20:02:00.052-0500
+2012-12-31T23:59:59,999999999+1100
+1970-01-01 00:00Z
+@end example
+