At what time did the agenda invented?
During what period was the agenda first introduced?
In which period was the calendar arise?
In which period was the timetable originally invented?
During what period did the timetable firstly imagined?
In what period was the calendar firstly devised?
In what period was the calendar generation?
When was the calendar come about for the first time?
Le calendrier mésoaméricain ancien temps partagé