Akpenpuun, T. D., K. A. Adeniran, B. A. Akinyemi, and O. O. Ologun. 2017. “Development and Performance Evaluation of a Poultry Waste Management Technique Using Gravity Sand Filter ”. ARID ZONE JOURNAL OF ENGINEERING, TECHNOLOGY AND ENVIRONMENT 13 (4), 502-12. https://azojete.com.ng/index.php/azojete/article/view/720.