R. V. Vershinin, “Imbedding of the images of operators and reflexivity of Banach spaces”, Ukr. Mat. Zhurn., vol. 51, no. 2, pp. 260–262, Feb. 1999, Accessed: Dec. 05, 2025. [Online]. Available: https://umj.imath.kiev.ua/index.php/umj/article/view/4606