Gan, Jia Ler, and Choon Yoong Cheok. 2021. “Enhanced Removal Efficiency of Methylene Blue and Water Hardness Using NaOH-Modified Durian and Passion Fruit Peel Adsorbents”. Progress in Energy and Environment 16 (January):36-44. https://www.akademiabaru.com/submit/index.php/progee/article/view/2951.