TY  - GEN
AU  - Hutchinson, T.B.
AU  - Kipps, M.S.
AU  - Wolfe, T.K.
TI  - Production of field crops : a text book of agronomy
U1  - 633 HUT 
CY  - New York, Mc Graw- Hill Book Company Inc
KW  - Crop production - economical aspects/ seeding practices/ crop rotation
ER  -