TY  - RPRT
TI  - An immunization model for a heterogeneous population.
AU  - H W Hethcote
PY  - 1978
DO  - 10.1016/0040-5809(78)90011-4
UR  - https://pubmed.ncbi.nlm.nih.gov/751264/
ID  - 751264
ER  -