BMJ. 1992 Mar 07;304(6827):639-40. doi: 10.1136/bmj.304.6827.639-c.
BMJ (Clinical research ed.)
D Neilson, P N Rao
PMID: 1559102 PMCID: PMC1881357 DOI: 10.1136/bmj.304.6827.639-c Free PMC Article
[No abstract available.]