TY  - RPRT
TI  - Problems in retrospectively evaluating a large-scale health intervention program.
AU  - M A Lavenhar
AU  - D O Gause
AU  - J Foster
AU  - D B Louria
PY  - 1981
DO  - 10.1007/bf01323008
UR  - https://pubmed.ncbi.nlm.nih.gov/7263939/
ID  - 7263939
ER  -