S. K. Kaushik and R. Kumar, “On $\boldsymbol{k}$-deficit Banach Frames. Armenian Journal of Mathematics”, Armen.J.Math., vol. 2, no. 4, pp. 146–154, Dec. 2009, Accessed: May 09, 2026. [Online]. Available: http://test.armjmath.sci.am/index.php/ajm/article/view/62