TY  - RPRT
TI  - Demographic changes as a problem for social security systems.
AU  - F Kaufmann
AU  - L Leisering
PY  - 1984
DO  - 10.1111/j.1468-246x.1984.tb00839.x
UR  - https://pubmed.ncbi.nlm.nih.gov/12340591/
ID  - 12340591
ER  -