1. Technical Report No. SDC 269-7-24;S. G. Allison,1951
2. Technical Report No. SDC 269-7-3;P. Ash,1949
3. Technical Report No. SDC 269-7-16;H. R. Brenner,1950
4. Hirsch, R. The effect of knowledge of results on learning from instructional sound films. Unpublished doctor's dissertation, Stanford University, 1951.
5. Technical Report No. SDC 269-7-19;C. F. Hoban,1950