TY - BOOK AU - Langdon,Danny G. TI - Interactive instructional designs for individualized learning SN - 0877780412 AV - LB1570 .L27 U1 - 371.39/43 PY - 1972///, c1973] CY - Englewood Cliffs, N.J. PB - Educational Technology Publications KW - Instructional systems KW - Design KW - Individualized instruction N1 - Bibliography: p. 146-147 ER -