Belovs, Mihails, and Jānis Smotrovs. “The Fourier‐asymptotic Approximation and Its Applications”. Mathematical Modelling and Analysis 3, no. 1 (December 15, 1998): 14-24. Accessed November 25, 2024. https://jau.vgtu.lt/index.php/MMA/article/view/9983.