TY  - RPRT
TI  - Perspective: cohort studies.
AU  - J M Samet
AU  - A Muñoz
PY  - 1998
DO  - 10.1093/oxfordjournals.epirev.a017968
UR  - https://pubmed.ncbi.nlm.nih.gov/9762516/
ID  - 9762516
ER  -