About: http://webisa.webdatacommons.org/38568004

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	The perpetual calendar is a mechanism that automatically takes into account the different number of days per month as well as leap years.
http://www.w3.org/ns/prov#wasQuotedFrom	issuu.com