·                     The Second Scientific Conference held in the Friendship Hall, Khartoum, Sudan, (12-24th January 1995).

·                     New Zealand Society of Soil Science, held in the University of Waikato, Hamilton, New Zealand (24-2ih November 1986).

·                     The 5th meeting of the East African Sub-Committee for Soil International Forum on Soil Taxonomy and Agrotechnology, held in Tunnis (2-11th September 1985).

·                   British Soil Science Society, Held in Abersywis, England, (Septembe1982).