TY  - BOOK
AU  -  B. Trecker, Harleigh.
TI  - Who to work with groups
U1  - 302.3 TRE-H 927 1965 
PY  - 1965///
CY  -  New York: 
PB  -  Mcgraw-Hill
KW  - principles of social group
KW  - Principal method
N1  - social group; Social Development
ER  -