Effect of organic manure on crop yield in long-term field experiments W.P. Wadman text Ind In: J.H. Cooley (ed), Soil organic matter dynamic and soil productivity: proc intend workshop, ekenaes, Sweden, 4-6 June 1986 Intern. Assoc. for ecology Athens... Intecol Bulletin 1987: 15 pp.83-89. In: J.H. Cooley (ed), Soil organic matter dynamic and soil productivity: proc intend workshop, ekenaes, Sweden, 4-6 June 1986 Intern. Assoc. for ecology Athens... Intecol Bulletin 1987: 15 pp.83-89. ORGANIC FERTILIZERS YIELDS EXPERIMENTS