Gasanenko, V. A., and A. B. Roitman. “Rarefaction of Moving Diffusion Particles”. Ukrains’kyi Matematychnyi Zhurnal 56, no. 5 (May 25, 2004): 691-694. Accessed May 8, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/3789.