PDS4 Information Model Classes	Semantic Types Ontology	Source
http://ontology.pds.nasa.gov/pds/0001_nasa_pds_1/pds/tagged_digital_child/pds/group	http://purl.bioontology.org/ontology/STY/T096	LOOM
http://ontology.pds.nasa.gov/pds/0001_nasa_pds_1/pds/data_object/pds/physical_object	http://purl.bioontology.org/ontology/STY/T072	LOOM