MIŠEIKIS, Feliksas. Approximation of characteristic functions in Rk spaces. Lietuvos matematikos rinkinys, [S. l.], v. 38, n. II, p. 514–516 , 1998. DOI: 10.15388/LMD.1998.37971. Disponível em: https://test.zurnalai.vu.lt/LMR/article/view/37971. Acesso em: 27 oct. 2025.