TY  - BK
AU  - De Vries,J.
TI  - Has extension failed? a case study of maize-growing practices in Iringa, Tanzania
T2  - Rural Economy Research Paper
PY  - 1975///
CY  - Morogoro (Tanzania)
PB  - Univ. of Dar es Salaam, Dept. of Rural Economy, 
ER  -