APA
                N Ningappa, N Vasuki Department of Soil Science and Agricultural Chemis, . (1987). Studies on fixation and influence of liming on the availability of potassium in some acid soils of Karnataka. Dharwad: University of Agricultural Sciences, Dharwad.
                
                Chicago
                N Ningappa, N Vasuki Department of Soil Science and Agricultural Chemis, . 1987. Studies on fixation and influence of liming on the availability of potassium in some acid soils of Karnataka. Dharwad: University of Agricultural Sciences, Dharwad.
                
                Harvard
                N Ningappa, N Vasuki Department of Soil Science and Agricultural Chemis, . (1987). Studies on fixation and influence of liming on the availability of potassium in some acid soils of Karnataka. Dharwad: University of Agricultural Sciences, Dharwad.
                
                MLA
                N Ningappa, N Vasuki Department of Soil Science and Agricultural Chemis, . Studies on fixation and influence of liming on the availability of potassium in some acid soils of Karnataka. Dharwad: University of Agricultural Sciences, Dharwad. 1987.