Medical NewsBr Med J 1939; 2 doi: http://dx.doi.org/10.1136/bmj.2.4108.711 (Published 30 September 1939) Cite this as: Br Med J 1939;2:711
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