HHEAR Value Sets Radiation Oncology Ontology Source
http://purl.obolibrary.org/obo/NCIT_C18020 http://ncicb.nci.nih.gov/xml/owl/EVS/Thesaurus.owl#C18020 LOOM
http://purl.obolibrary.org/obo/NCIT_C18020 http://purl.bioontology.org/ontology/STY/T060 LOOM