IETFのXML日付形式

History

Time	Change
2014-05-07 12:10:53+00:00	Created
2014-05-07 12:10:53+00:00	Associated with 21834
2017-04-25 10:06:54+00:00	Disassociated from 21834
2017-04-25 10:06:59+00:00	Associated with 206