TY  - BOOK
AU  - Sommer Robert
AU  -  Sommer Barbara B.
TI  - Practical guide to behavioral reseach Tools and techniques
U1  - SN1:f, M0 
PY  - 1980///
CY  - New York
PB  - Oxford University Press    
KW  - PSYCHOLOGY
N1  - Appendix p 241--250 (AD)
ER  -