Gregorian calendar WikipediaWhen was the timetable invented?
At what time was the agenda initially developed?
During what period did the calendar come into existence?
During what period was the timetable originally invented?
During what period was the timetable originally thought up?
During what period was the timetable firstly introduced?
During what period was the calendar generation?
When did the timetable come about for the first time?
