Union of http://hl7.org/fhir/ValueSet/forms and http://hl7.org/fhir/ValueSet/forms
This is the ValueSet that contains all the codes in Forms (http://hl7.org/fhir/ValueSet/forms) and Forms (http://hl7.org/fhir/ValueSet/forms). E.g. what you have to deal with if you get resources containing codes in either of them