Measurement Method Ontology	Pregnancy Information Needs Ontology	Source
http://www.semanticweb.org/luyu/ontologies/2021/3/pregnancy_information_needs_ontology#Echocardiography	http://purl.obolibrary.org/obo/MMO_0000337	LOOM
http://www.semanticweb.org/luyu/ontologies/2021/3/pregnancy_information_needs_ontology#Electrocardiography	http://purl.obolibrary.org/obo/MMO_0000003	LOOM