By Julian Simon
By Gemma Fowler
By M.K. Jenyon
By Dorte Verner
By Philip Lymbery
By Mark Everard
By Jon Bowermaster, Participant Participant Media
By BMJ
By John Hills
By Howard Peavy
By T. Cairney
By Sir Bryan Cartledge (Principal, Lineacre College, Oxford)
By Prof. R E Hester (University of York, UK), Prof. R M Harrison (University of Birmingham
By Jack B. Carmichael, Kenneth M. Strzepek
By Hester, R E, Harrison, R M
By John M. Hartwick, Nancy D. Olewiler
By Great Britain: Department of the Environment
By G. Cornelis Van Kooten, Erwin H. Bulte
By Guy P.F. Robinson
By Keith Kirby (Oxford University, UK), Charles Watkins (School of Geography, University of Nottingham
By A. J. Grayson (former Director of Research, forestry commission, Great Britain, on behalf of the Scottish Forestry Trust)
By H. Zoebelein
By Donald G. Reid (University of Guelph, Canada)
By Professor Tom Tietenberg
By J. Beattie
By Gareth Jones
By Christian Ludwig, Stefanie Hellweg, Samuel Stucki
By David E. Camacho
By Professor of Anthropology Brian Fagan (University of California USA)