NURGABYL, D.N.; NAZHIM, S.S. Recovery problem for a singularly perturbed differential equation with an initial jump. Bulletin of the Karaganda University. Mathematics Series, [S. l.], v. 100, n. 4, p. 125–135, 2020. DOI: 10.31489/2020m4/125-135. Disponível em: http://mts.buketov.edu.kz/index.php/mathematics-vestnik/article/view/392. Acesso em: 4 sep. 2025.