"Do not think, but try; be patient, be accurate".
Massey
R U
RU
Department of Community Medicine and Health Care, University of Connecticut School of Medicine, Farmington, USA.
D049671:History, 18th Century; D049673:History, 20th Century; D049690:History, Ancient; D049691:History, Medieval; D006801:Humans; D012899:Smallpox / Q000266:history; D012900:Smallpox Vaccine / Q000266:history*
D012900:Smallpox Vaccine