All Over the WorldBr Med J 1951; 1 doi: http://dx.doi.org/10.1136/bmj.1.4718.1307 (Published 09 June 1951) Cite this as: Br Med J 1951;1:1307
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