EPIDEMIOLOGICAL NOTESBr Med J 1939; 2 doi: https://doi.org/10.1136/bmj.2.4121.1300-a (Published 30 December 1939) Cite this as: Br Med J 1939;2:1300
Log in using your username and password
Log in through your institution
Register for a free trial to thebmj.com to receive unlimited access to all content on thebmj.com for 14 days.
Sign up for a free trial