TY  - BOOK
AU  - Cook,Thomas D.
AU  - Campbell,Donald T.
TI  - Quasi-experimentation : design & analysis issues for field settings
AV  - H62 C664Q
PY  - 1979///
CY  - Boston, Mass.
PB  - 
KW  - SOCIAL SCIENCES
KW  - RESEARCH DESIGN
KW  - RESEARCH
KW  - FIELD WORK
ER  -