[1]
“The contribution of Nikola Obreshkoff to the theory of diophantine approximation”, Ann. Sofia Univ. Fac. Math. and Inf., vol. 89, pp. 47–58, Dec. 1997, Accessed: Dec. 14, 2025. [Online]. Available: https://annual.uni-sofia.bg/index.php/fmi/article/view/354