An invitation from CPHA.
D002170:Canada; D049672:History, 19th Century; D049673:History, 20th Century; D049674:History, 21st Century; D006801:Humans; D009740:Nursing Staff / Q000266:history*; D011634:Public Health / Q000266:history*; D011637:Public Health Nursing / Q000266:history*; D012955:Societies, Medical / Q000266:history