IvashchukO. V. and ZadereiP. V. (2011) “On necessary conditions for the convergence of Fourier series”, Ukrains’kyi Matematychnyi Zhurnal, 63(7), pp. 960-968. Available at: https://umj.imath.kiev.ua/index.php/umj/article/view/2777 (Accessed: 1September2024).