@INBOOK {JUO:1989, title = {Nutrient effects of modification of shifting cultivation in west Africa}, author = {Juo, A. S. R. and Kang, B. T. }, year = {1989}, type = {Mineral nutrients in tropical forest and savanna ecosystems}, pages = {289--300}, publisher = {Blackwell}, isbn = {0-632-02559-X}, note = {In: Mineral nutrients in tropical forest and savanna ecosystems}, }