TY  - RPRT
TI  - Implications of the activity factor.
AU  - M E Hoppa
AU  - G D Roberts
PY  - 1974
DO  - 10.1093/geront/14.4.331
UR  - https://pubmed.ncbi.nlm.nih.gov/4470515/
ID  - 4470515
ER  -