НЕЛІН, Є. А.; ШУЛЬГА, А. В. Criteria of impedance inhomogeneities approaching by delta-inhomogeneities. Visnyk NTUU KPI Seriia - Radiotekhnika Radioaparatobuduvannia, [S. l.], n. 63, p. 127-135, 2015. DOI: 10.20535/RADAP.2015.63.127-135. Disponível em: http://radap.kpi.ua/radiotechnique/article/view/1157. Acesso em: 20 jun. 2021.