TY  - BOOK
AU  - Roberts, Fred S.
TI  - Discrete mathematical models: with applications to social, biological, and environmental problems 
SN  - 013214171X
PY  - 1976///
CY  - Englewood Cliffs
PB  - Prentice-Hall
KW  - Biology
KW  - Mathematical models
KW  - Social sciences
N1  - Includes Indexes
ER  -