Zagorodnii A.G., Samoilenko A.M., Bugrov V.A., Mel’nykV.P., Zgurovs’kyi M.Z., Stricha M.V. and Virchenko N.O. 2022. On the 100th birthday of outstanding scientist Ostap Stepanovych Parasyuk (20.12.1921 – 22.11.2007). Ukrains’kyi Matematychnyi Zhurnal. 74, 2 (Feb. 2022), 286 - 288. DOI:https://doi.org/10.37863/umzh.v74i2.6873.