TY  - BOOK
AU  - Smith David
AU  -  Keyfitz Nathan
TI  - Mathematical demography:  Selected papers   
T2  - Biomathematics. 6
U1  - Y:5:(B), L7 
PY  - 1977///
CY  - New York
PB  - Springer Verlag        
KW  - Family Planning
N1  - Bibliography chapterwise: p 501-506
ER  -