Lal, Nand, and Hemlata Singh. “The Effects of Simulated Acid Rain of Different PH-Levels on Biomass and Leaf Area in Sunflower (Helianthus Annuus)”. Current Botany 3, no. 5 (April 15, 2013). Accessed September 22, 2025. https://www.updatepublishing.com/journal/index.php/cb/article/view/1434.