TY  - BOOK
AU  - Thelen,Herbert A.
TI  - Classroom grouping for teachability
U1  - 371.39 
PY  - 1967///
CY  - New York
PB  - John Wiley
KW  - Ability grouping in education
KW  - Teacher-student relationships
KW  - Grouping
KW  - ability
N1  - Includes bibliographical references and index
ER  -