TY  - BOOK
AU  - Frankenberger, Timothy R.
ED  - The Association for farming System Research Extension.
TI  - Journal for farming systems research extension (Vol 4, No 1)
U1  - Journal. 
PY  - 1993///
CY  - Tucson;
PB  - The University of Arizona
KW  - Journal on farming system
N1  - Includes references
ER  -