Čiegis, Raimondas, Genė Kairytė, and Violeta Pakalnytė. “On Nonlinear Schrödinger Problem With Amplification Process”. Lietuvos matematikos rinkinys 40, no. spec. (December 18, 2000): 337–342. Accessed August 16, 2024. https://www.journals.vu.lt/LMR/article/view/35172.