BMJ. 1992 Mar 14;304(6828):711. doi: 10.1136/bmj.304.6828.711.
BMJ (Clinical research ed.)
K K Cheng, N E Day
PMID: 1497716 PMCID: PMC1881539 DOI: 10.1136/bmj.304.6828.711 Free PMC Article
[No abstract available.]