ZSCHORN, S. NONSELFADJOINT DEGENERATE DIFFERENTIAL OPERATOR EQUATIONS OF HIGHER ORDER ON INFINITE INTERVAL. Proceedings of the YSU A: Physical and Mathematical Sciences, Yerevan, Armenia, v. 48, n. 2 (234), p. 39–45, 2014. DOI: 10.46991/PSYU:A/2014.48.2.039. Disponível em: https://journals.ysu.am/index.php/proceedings-phys-math/article/view/vol48_no2_2014_pp039-045. Acesso em: 22 jul. 2024.