By Bishop, Alan Wilfred, Henkel, D.J., Alan Wilfred Bishop, D.J. Henkel
By Tim Smit
By M.B. Green, D.J.De B. Lyon
By G.Clifford Evans
By Food and Agriculture Organization of the United Nations
By M. N. Clifford, K. C. Willson
By Are, L. A., Jones, D.R.G.Gwynne-
By G. M. Craig (Research Fellow, Centre for Agricultural Strategy, University of Reading)
By Dennis S. Hill, J. M. Waller
By J.M. Hodgson
By F. N. Howes
By Melvyn Kay
By Raymond A. T. George
By Trevor Martin
By P. S. Nutman
By L. T. Evans
By Agriculture, Fish.& Food, Min.of
By RA Lelliott (Dunez, Head of the Plant Pathology Station, INRA, Bordeaux; D.), D. Stead
By N.W. Simmonds
By T.A. Phillips
By R. J. Garner, etc., et al