This is the ValueSet that contains all the codes in AU eRequesting CommunicationRequest Patient Medium (http://hl7.org.au/fhir/ereq/ValueSet/au-erequesting-communicationrequest-patientmedium) and AU eRequesting CommunicationRequest Patient Medium (http://hl7.org.au/fhir/ereq/ValueSet/au-erequesting-communicationrequest-patientmedium). E.g. what you have to deal with if you get resources containing codes in either of them