Ansari, A.A., and V.K. Chaudhry. “On Köthe-Toeplitz Duals of Some New and Generalized Difference Sequence Spaces”. Italian Journal of Pure and Applied Mathematics 29 (December 11, 2012): 135–148. Accessed July 18, 2026. https://journals.uniurb.it/index.php/ijpam/article/view/6049.