5912
6755
Spedding, C.R.W
Biological efficiency in agriculture
London; New York
Academic Press
1981
x, 383p.: ill
Includes bibliographies and index
C.R.W. Speeding, J.M. Walsingham, and A.M. Hoxey
، Agricultural productivity
، Biological productivity
، Agriculture
، Biology, Economic
S
494
.
5
.
P75
S63
AU
AU Walsingham, J.M.
CO Hoxey A.M
TI
CL
CL
