TY  - BOOK
AU  - Roberts, Fred S.
TI  - Discrete Mathematical Models : with applications to social, biological and environmental problems 
SN  - 013214171X
AV  - QH3235  .R63 1976
PY  - 1976///
CY  - New Jersey
PB  - Prentice- Hall 
KW  - Biology
KW  - mathematical models
KW  - Social sciences
ER  -