EPIDEMIOLOGY SECTIONBr Med J 1940; 1 doi: http://dx.doi.org/10.1136/bmj.1.4146.1041 (Published 22 June 1940) Cite this as: Br Med J 1940;1:1041
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