<https://faq.mailo.com/agenda/supprimer-agenda-principal-ou-rendre-principal-un-agenda-secondaire.htm#webpage>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://faq.mailo.com/agenda/supprimer-agenda-principal-ou-rendre-principal-un-agenda-secondaire.htm>