Полях, О., and Н. Ястребов. “Features of Finding Resonance Frequencies Systems of Coupled Circuits”. Visnyk NTUU KPI Seriia - Radiotekhnika Radioaparatobuduvannia, no. 41, Oct. 2010, pp. 12-18, doi:10.20535/RADAP.2010.41.12-18.