Sonar--the story of an experiment.
D005260:Female; D005333:Fetus / Q000033:anatomy & histology / Q000502:physiology; D006257:Head / Q000033:anatomy & histology; D049673:History, 20th Century; D006801:Humans; D006828:Hydatidiform Mole / Q000175:diagnosis; D010048:Ovarian Cysts / Q000175:diagnosis; D011247:Pregnancy; D012606:Scotland; D014465:Ultrasonics / Q000266:history; D014463:Ultrasonography