BMJ. 1991 Oct 05;303(6806):838-40. doi: 10.1136/bmj.303.6806.838.
BMJ (Clinical research ed.)
S Lowry
PMID: 1932978 PMCID: PMC1671182 DOI: 10.1136/bmj.303.6806.838 Free PMC Article
[No abstract available.]