TY  - BOOK
AU  - Leedham,John
AU  - Unwin,Derick
TI  - Programmed learning in the schools
SN  - 0582320917
PY  - 1971///
CY  - London: 
PB  - Longman Group, 
KW  - Programmed instruction
N1  - Bibliography: pages 133-134
ER  -