Description
Bibliography:ark:/67375/NVC-N0HD3GVJ-D
istex:857C8F78D5DA40487F86B610B4534D09D00591B8
local:bmj;1/3763/286
href:bmj-1-286-1.pdf
ISSN:0007-1447
1468-5833
DOI:10.1136/bmj.1.3763.286