AU  - Green,Detroy E.
AU  - Woolley, D.G
TI  - Audio tutorial systems / 
T2  - Agronomy Series, 
U1  - 371.3302463 
PY  - 1970///
CY  - Minneapolis : 
PB  - Burgess Publishing , 
KW  - Audio Visual Materials for Teaching
KW  - Audio Totorial Systems
ER  -