Muhammad Faisal, R. “Buckyball Derivatives As Acceptors in Organic Photovoltaics: A Review”. International Journal of Formal Sciences: Current and Future Research Trends, vol. 13, no. 1, Apr. 2022, pp. 119-4, https://ijfscfrtjournal.isrra.org/index.php/Formal_Sciences_Journal/article/view/646.