TY  - BOOK
AU  - Cook,Thomas D.
AU  - Campbell,Donald T.
TI  - Quasi-experimentation: design & analysis issues for field settings 
SN  - 0395307902
AV  - H62.C66 1979 
PY  - 1979///
CY  - Boston
PB  - Houghton Mifflin Company
KW  - Social sciences
KW  - Research
KW  - Fieldwork
N1  - Includes index; Bibliography: p. 387-396
ER  -