N. V. Zorii, “A noncompact variational problem in the theory of riesz potentials. II”, Ukr. Mat. Zhurn., vol. 48, no. 5, pp. 603–613, May 1996, Accessed: Feb. 17, 2026. [Online]. Available: https://umj.imath.kiev.ua/index.php/umj/article/view/5293