s. Vol. 2 (Eds M. K. van Ittersum, G. E. G. T. Venner, S. C. van de Geijn & T. H. Jetten), pp. 438–439.WILLIAMS,M. M.,MORTENSEN,D. A.&DORAN;, J. W. (1998).Assessment of weed and crop fitness in cover crop residues for integrated weed management. Weed Science 46, 595–603.YOUNIE, D., WATSON, C. A. & SQUIRE, G. R. (1996). Acomparison of crop rotations in organic farming: agronomic p...