YURKO, V. Inverse spectral problems for differential operators on a graph with a rooted cycle. Tamkang Journal of Mathematics, [S. l.], v. 40, n. 3, p. 271–286, 2009. DOI: 10.5556/j.tkjm.40.2009.506. Disponível em: https://journals.math.tku.edu.tw/index.php/TKJM/article/view/506. Acesso em: 22 jul. 2024.