The Maya Calendar System Smithsonian InstitutionDuring what period did the agenda originated?
In what period was the timetable initially devised?
In which period did the calendar come into existence?
At what time was the calendar initially devised?
During what period did the calendar initially imagined?
During what period was the
calendar firstly devised?
In what period was the calendar inception?
In what period was the calendar come about for the first time?