TY  - RPRT
TI  - Practice variations by population: training significance.
AU  - R D Feigin
AU  - J E Drutz
AU  - E O Smith
AU  - C R Collins
PY  - 1996
UR  - https://pubmed.ncbi.nlm.nih.gov/8692615/
ID  - 8692615
ER  -