Tripathi, Gyan Prakash, and Nand Lal. “Antinormal Composition Operators on $ \mbf{\ell^2}$”. Tamkang Journal of Mathematics 39, no. 4 (December 1, 2008): 347–352. Accessed April 3, 2025. https://journals.math.tku.edu.tw/index.php/TKJM/article/view/9.