TY  - BOOK
AU  - Grigg,David B.
TI  - The agricultural systems of the world: an evolutionary approach 
SN  - 0521098432
AV  - S 439 G857a 1974
U1  - 630/.9 
PY  - 1974///
CY  - London, New York
PB  - Cambridge University Press
KW  - Agricultural geography
KW  - Agriculture
KW  - History
KW  - Geografía agrícola
KW  - Agricultura
KW  - Historia
ER  -