SokolenkoI. V. “Approximation of $\bar {\omega}$ -Integrals of Continuous Functions Defined on the Real Axis by Fourier Operators”. Ukrains’kyi Matematychnyi Zhurnal, Vol. 56, no. 5, May 2004, pp. 663-76, https://umj.imath.kiev.ua/index.php/umj/article/view/3786.