海量图书期刊资源,随时随地畅享阅读乐趣
Effects of temperature and photoperiod on phenology as a guide to the selection of annual legume cover and green manure crops for hillside farming systemsJ.D.H Keatinge; Aiming Qi; T.R Wheeler; R.H Ellis; R.J Summerfield · 1998
A walk-through weigher for dairy cowsD.E. Filby; M.J.B. Turner; M.J. Street · 1979