2017年04月 / Counting down to Christmas A history of the Advent Calendar
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During what period did the timetable devised?
In what period did the agenda initially developed?
In which period was the schedule come into existence?
When did the timetable firstly invented?
During what period did the schedule originally imagined?
At what time was the timetable initially devised?
During what period did the timetable inception?
In what period was the calendar come about for the first time?