Union of http://terminology.hl7.org/CodeSystem/CAS and http://terminology.hl7.org/CodeSystem/CAS

This is the CodeSystem that contains all the codes in Chemical abstract codes (http://terminology.hl7.org/CodeSystem/CAS) and Chemical abstract codes (http://terminology.hl7.org/CodeSystem/CAS). E.g. what you have to deal with if you get resources containing codes in either of them

CodeSystem

Generated Narrative: CodeSystem d1c8b6ec-a80e-4fac-a75a-4c2360d0fb6d-56

This code system http://hl7.org/fhir/comparison/CodeSystem/d1c8b6ec-a80e-4fac-a75a-4c2360d0fb6d-56 defines codes, but no codes are represented here

Code