TY  - BOOK
AU  - Gagne Robert M.
AU  -  Briggs Leslie J.
TI  - Principles of instructional design
SN  - 0-03-008171-8
PY  - 1974///
CY  - New York, USA
PB  - Holt, Rinehart and Winston 
KW  - Psychology -Learning
ER  -