This is a linked open data (LOD) about date and time. "18/05/1441" is a date of Hijri Calendar-TEST (Calendar ID: 9103.1).
http://datetime.hutime.org/calendar/9103.1/date/18/05/1441
hcal:9103.1/date/2458862.5
hcal:9103.1/date/18/05/1441
hcaldate:2458862.5
hcaldate:18/05/1441