HrabovaU. Z., KalchukI. V. and StepanyukT. A. (2017) “Approximation of functions from the classes $W_{β}^r H^{α }$ by Weierstrass integrals”, Ukrains’kyi Matematychnyi Zhurnal, 69(4), pp. 510-519. Available at: http://umj.imath.kiev.ua/index.php/umj/article/view/1712 (Accessed: 30November2020).