Khirina, G. and Savchenko, A. (2022) “The story of three letters. Spiritual relay of the generations. V. N. Karazin – E. I. Koltunovsky – M. F. Sumtsov”, V. N. Karazin Kharkiv National University Bulletin ‘History of Ukraine. Ukrainian Studies: Historical and Philosophical Sciences’, 35, pp. 45-50. doi: 10.26565/2227-6505-2022-35-05.