F. Usman, “DISTRIBUTION AND SIGNIFICANCE OF HEAVY METALS IN SOME COALS FROM BENUE TROUGH”, FJS, vol. 2, no. 1, pp. 231–237, Mar. 2023, Accessed: Oct. 29, 2025. [Online]. Available: http://www.fjsadmin.fudutsinma.edu.ng/index.php/fjs/article/view/1303