TY  - RPRT
TI  - Statistics notes. Trials randomised in clusters.
AU  - J M Bland
AU  - S M Kerry
PY  - 1997
DO  - 10.1136/bmj.315.7108.600
UR  - https://pubmed.ncbi.nlm.nih.gov/9302962/
ID  - 9302962
ER  -