In which period was the timetable invented?
When did the calendar initially established?
During what period did the timetable emerge?
In what period did the agenda originally devised?
In which period was the calendar initially thought up?
In which period did the agenda initially established?
In what period was the schedule inception?
When did the agenda come about for the first time?
Mesoamericans Have Been Using a 260Day Ceremonial Calendar
