History

Time	Change
2017-01-05 14:48:37+00:00	Created
2017-01-05 14:48:37+00:00	Associated with 時圏
2017-01-05 14:48:50+00:00	Associated with 時円
2017-01-05 14:48:50+00:00	Associated with 時角圏
2017-01-05 15:43:38+00:00	Associated with hour circle