A Systematic Review: Down-flow Hanging Sponge Application for Wastewater Treatment Technology. Nusantara Science and Technology Proceedings, Malang, Indonesia, p. 159–165, 2021. DOI: 10.11594/nstp.2021.1425. Disponível em: https://nstproceeding.com/index.php/nuscientech/article/view/502. Acesso em: 25 apr. 2025.