Norazreen Sharip, Siti Nazirah Abdul Malek, Nurul Fatihah Syahronie, Nurish Alysa Sofea Roslan. Synthesis of Eco-Friendly Inks from Waste Cooking Oil: Evaluating the Properties of Charcoal and Butterfly Pea Flower Formulations . Future Energy Environ. Lett. [Internet]. 2026 Jun. 22 [cited 2026 Jul. 26];7(1):1-7. Available from: https://karyailham.com.my/index.php/feel/article/view/1126