Shcherbak, V. (2016). The Reforms of Hetman of Zaporozhian Army Petro Sagaydachnyi and Kyiv Metropolitan Petro Mohyla in he Context of the “Rus’ People” Concept Formation. History Notebooks, 2016, 287-294. doi: https://doi.org/10.4467/20844069PH.16.007.5056