Vasilyeva, L., Y. Zhileikin, and Y. Osipik. “Fourier and Wavelet Transforms. Properties and Applications”. Numerical Methods and Programming (Vychislitel’nye Metody I Programmirovanie), vol. 3, no. 3, Oct. 2002, pp. 172-5, https://en.num-meth.ru/index.php/journal/article/view/57.