TY  - RPRT
TI  - Computations for group sequential boundaries using the Lan-DeMets spending function method.
AU  - D M Reboussin
AU  - D L DeMets
AU  - K M Kim
AU  - K K Lan
PY  - 2000
DO  - 10.1016/s0197-2456(00)00057-x
UR  - https://pubmed.ncbi.nlm.nih.gov/10822118/
ID  - 10822118
ER  -