Kumagai, Satoshi, and Ryusei Fujii. “Constrained Minimum Variance Portfolio Considering Investors’ Environmental, Social, and Governance Preferences”. International Journal of Economics and Financial Issues 15, no. 5 (August 25, 2025): 88–95. Accessed December 5, 2025. https://econjournals.com/index.php/ijefi/article/view/19397.