TY  - RPRT
TI  - Observational evidence.
AU  - C H Hennekens
AU  - J E Buring
PY  - 1993
DO  - 10.1111/j.1749-6632.1993.tb26330.x
UR  - https://pubmed.ncbi.nlm.nih.gov/8192295/
ID  - 8192295
ER  -