Description: Date specification related to a fixed date; Name: calendar validity from
Description: appointment information covered to a fixed date; Name: calendrical validity from
Description: The norm in fixed relation to the feature being described. This defines the parameters that influence the contents of the correlated feature. Type and number of the norm with issue year and issue month must be given, e.g. DIN ISO 4711:YYYY-MM.; Name: Reference norm of the connection, muff A2