Rajesh K. THUMBAKARA. Studies on Quotient Frames and Filters. Theory and Practice of Mathematics and Computer Science Vol. 7, [S. l.], p. 133–138, 2021. DOI: 10.9734/bpi/tpmcs/v7/7070D. Disponível em: https://stm.bookpi.org/TPMCS-V7/article/view/162. Acesso em: 4 jun. 2026.