“Effects of Tillage Practices, Cropping Systems and Organic Inputs on Soil Nutrient Content in Machakos County, Kenya”, GJSFR, vol. 18, no. D6, pp. 23–35, Sep. 2018, Accessed: Aug. 14, 2026. [Online]. Available: https://www.journalofscience.org/index.php/GJSFR/article/view/2356