JAIN, P. K., and D. P. SINHA. “SOME CHARACTERIZATIONS OF UNCONDITIONAL SCHAUDER DECOMPOSITIONS OF BANACH SPACES”. Tamkang Journal of Mathematics 21, no. 4 (December 1, 1990): 359–363. Accessed April 24, 2024. https://journals.math.tku.edu.tw/index.php/TKJM/article/view/4683.