TY  - BOOK
AU  - DUNNING Thad
TI  - Natural experiments in the social sciences:  A design- based approach   
SN  - 9781107698000
U1  - Yb4, Q2 
PY  - 2012///
CY  - New York
PB  - Cambridge University Press       
KW  - Economics
N1  - Bibliography: 357-378p
ER  -