Union of http://terminology.hl7.org/ValueSet/v3-GTIN and http://terminology.hl7.org/ValueSet/v3-GTIN
This is the ValueSet that contains all the codes in GTIN (http://terminology.hl7.org/ValueSet/v3-GTIN) and GTIN (http://terminology.hl7.org/ValueSet/v3-GTIN). E.g. what you have to deal with if you get resources containing codes in either of them