“Monitoring Heavy Metal Pollution at Al-Buraihi Sewage Station in Taiz, Yemen Using Napier Grass (Pennisetum Purpureum Schumach) As a Bioindicator”. European Journal of Engineering Science and Technology 4, no. 2 (December 20, 2021): 14–33. Accessed October 26, 2025. http://dpublication.com/journal/index.php/EJEST/article/view/433.