L. Haruna, A. A. Safana, I. M. Musa, H. Y. Hafeez, U. M. Dankawu, and M. M. Machina, “Effect of Temperature and Retention Time on the Quality of Biochar of Some Agricultural Waste”, NJP, vol. 35, no. 4, pp. 1–7, Jul. 2026, doi: 10.62292/njp.v35i4.2026.600.