ZAENAL, Muhammad Hasbi et al. Baznas Index For Sustainability of Clean Water and Sanitation (BI-WAS). Publications | BAZNAS Research and Development Directorate, [S.l.], v. 4, jan. 2020. Available at: <http://www.iconzbaznas.com/publications/index.php/books/article/view/128>. Date accessed: 16 nov. 2025.