MODEL OF THE INDEX SYSTEM FOR ASSESSING THE SUSTAINABLE DEVELOPMENT OF UKRAINIAN OIL AND GAS COMPANIES Authors D. Nikolaiev https://orcid.org/0000-0002-7563-5962 DOI: https://doi.org/10.32702/2306-6814.2026.4.231 Downloads pdf (Українська) Published 2026-02-17 Issue No. 4 (2026): Investytsiyi: praktyka ta dosvid Section Статті