Authors: A T Willis; I R Ferguson; P H Jones; K D Phillips; P V Tearle; R V Fiddian; D F Graham; D H Harland; D F Hughes; D Knight; W M Mee; N Pashby; R L Rothwell-Jackson; A K Sachdeva; I Sutch; C Kilbey; D Edwards Journal: Br Med J Date: 1977-03-05