TY  - BOOK
AU  - Davis,Robert H.
AU  - Alexander,Lawrence T.
AU  - Yelon,Stephen L.
TI  - Learning system design: an approach to the improvement of instruction 
SN  - 0070743347
PY  - 1974///
CY  - New York
PB  - McGraw-Hill
KW  - Instructional systems
KW  - Design
N1  - Bibliography: p. 331
ER  -