International Symposium on Distribution, Characteristics, and Utilization of Problem Soils : proceedings of a symposium on tropical agriculture research, Tsukuba, October 19-26, 1981. - International Symposium on Distribution, Characteristics, and Utilization of Problem Soils ( 1981 : Tsukuba Kenkyu Gakuen Toshi, Japan). (Tokyo : Japanese Society of Soil Science and Plant Nutrition, 1982)
Keywords: Problem soils -- Congresses; Soils -- Tropics -- Congresses