KotovaO. V., and TrigubR. M. “A New Sufficient Condition for Belonging to the Algebra of Absolutely Convergent Fourier Integrals and Its Application to the Problems of Summability of Double Fourier Series”. Ukrains’kyi Matematychnyi Zhurnal 67, no. 8 (August 25, 2015): 1082-1096. Accessed November 21, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/2047.