TY  - RPRT
TI  - Variation in human fertility.
AU  - O Mayo
AU  - M M Nelson
AU  - J O Forfar
PY  - 1973
DO  - 10.1159/000152605
UR  - https://pubmed.ncbi.nlm.nih.gov/4785871/
ID  - 4785871
ER  -