title: The zygosity of twins: further evidence on the agreement between diagnosis by blood groups and written questionnaires.
mesh_terms: D000328:Adult; D001789:Blood Group Antigens; D005260:Female; D006801:Humans; D008297:Male; D011247:Pregnancy; D013008:Somatotypes; D011795:Surveys and Questionnaires; D014427:Twins; D014429:Twins, Dizygotic; D014430:Twins, Monozygotic
chemical_list: D001789:Blood Group Antigens