USTIMENKO, V. On multivariate public keys based on a pair of transformations with density gap . Reports of the National Academy of Sciences of Ukraine, Kyiv, Ukraine, n. 9, p. 21–27, 2024. DOI: 10.15407/dopovidi2018.09.021. Disponível em: https://nasu-periodicals.org.ua/index.php/dp/article/view/3004. Acesso em: 18 apr. 2026.