TY  - RPRT
TI  - Causal inference in a clinical trial: a comparative example.
AU  - D F Heitjan
PY  - 1999
DO  - 10.1016/s0197-2456(99)00012-4
UR  - https://pubmed.ncbi.nlm.nih.gov/10440558/
ID  - 10440558
ER  -