2019-08-15 The Open Group Federated Freebusy Challenge Demo V1.0 (CD 0608) CC/Adm 0608:2006 pubdocs/CD0608%20The%20Open%20Group%20Federated%20Freebusy%20Challenge%20Demo%20V1.0.pdf 2006-07-17 published FREEBUSY