<https://mylearningsolutions.org/2014/09/26/working-with-dates-and-days-of-the-week-in-excel/#organization>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://mylearningsolutions.org/2014/09/26/working-with-dates-and-days-of-the-week-in-excel/>