“Greener Pretreatment and the Characterization of Neem and Babul Tree Barks for Lignin Extraction ”. International Journal of Sustainable Energy and Environmental Research 14, no. 2 (December 1, 2025): 90–103. Accessed September 14, 2026. https://archive.conscientiabeam.com/index.php/13/article/view/4555.