FIRST OIL FIELD DISCOVERED BY "NAFTOGAZ OF UKRAINE" NATIONAL JOINTBSTOCK COMPANY IN DNIEPER-DONETS DEPRESSION by ZEYKAN, O.Yu., GLADUN, V.V., MAKSYMCHUK, P.Ya., CHEPIL, P.M., DUDNIKOV, M.S., GUSACHENKO, V.O., DOVZHOK, T.E., VAKARCHUK, S.G., KHARCHENKO, N.V., STRYZHAK, V.P., SHEVCHENKO, O.A.