SYROVATSKY, A. The inverse spectral task for a self-adjoint differential operator at a one-dimensional perturbation . Reports of the National Academy of Sciences of Ukraine, Kyiv, Ukraine, n. 1, p. 27–32, 2025. DOI: 10.15407/dopovidi2014.01.027. Disponível em: https://nasu-periodicals.org.ua/index.php/dp/article/view/17404. Acesso em: 19 apr. 2026.