Iqbal, Muhammad Naeem, and Asfa Ashraf. “Recent Trends in Animal Fats and Oils to Biodiesel Research: Conversion Methods, Technical Challenges and Assessment of Economic and Environmental Impacts”. International Journal of Alternative Fuels and Energy 1, no. 1 (December 14, 2017): 21–22. Accessed May 15, 2024. https://psmjournals.org/index.php/ijafe/article/view/142.