Samoilenko A.M., Kushnir R.M., Makarov V.L., Perestyuk M.O., Sharkovs’kyi O.M., Boichuk O.A., Hutlyans’kyi V.J., Kit H.S., Nikitin A.G., Portenko M.І., Slyusarchuk V.Y. and TimokhaO.M. 2020. Ivan Oleksandrovych Lukovs’kyi (on his 85th birthday). Ukrains’kyi Matematychnyi Zhurnal. 72, 12 (Dec. 2020), 1721-1723. DOI:https://doi.org/10.37863/umzh.v72i10.6318.