This is a linked open data (LOD) about date and time. "C.E. 1679 February 11" is a date of Julian/Gregorian Calendar (reformed in 1582) (Calendar ID: 101.1).
http://datetime.hutime.org/calendar/101.1/date/C.E._1679_February_11
hcal:101.1/date/2334343.5
hcal:101.1/date/C.E._1679_February_11
hcaldate:2334343.5
hcaldate:C.E._1679_February_11