GUPTA, M. K.; MANOJ, Kumar; RUPEN, Pratap Singh. A note on mixed summation-integral-type operators. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 59, n. 8, p. 1135–1139, 2007. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/3376. Acesso em: 6 dec. 2025.