BMJ. 1989 Apr 01;298(6677):847-8. doi: 10.1136/bmj.298.6677.847.
BMJ (Clinical research ed.)
A B Shrank
PMID: 2497819 PMCID: PMC1836128 DOI: 10.1136/bmj.298.6677.847 Free PMC Article
[No abstract available.]