TY  - BOOK
AU  - Cook,Thomas D.
AU  - Campbell,Donald T.
TI  - Quasi-experimentation: design & analysis issues for field settings 
AV  - H62 .C5857 1979
PY  - 1979///
CY  - Boston
PB  - Houghton Mifflin Co.
KW  - Social sciences
KW  - Research
KW  - Fieldwork
N1  - Includes bibliographical references and index
ER  -