TY  - BOOK
AU  - Keyeitz Nathan
AU  -  Beekman John A
TI  - Demography through problems
T2  - Problem Books in Mathematics
SN  - 0387908366
U1  - Y:5:(B), M4 
PY  - 1984///
CY  - New York
PB  - Springer-Verlag         
KW  - Family Planning
N1  - Bibliography: p  135-136
ER  -