At what time was the agenda created?
In which period did the agenda first developed?
During what period was the timetable emerge?
In which period did the timetable firstly created?
During what period was the timetable firstly conceived?
During what period was the
calendar firstly devised?
At what time was the timetable generation?
In which period was the timetable arise for the first time?
The history of calendars
