00607naa#a2200181#i#450# EN\\bibl\49127 20240504041958.6 2071-7318 20220614b2022####ek#y0engy0150####ca RU RESEARCH OF TIME OF CRITICAL ILLUMINATION TO ASSESS THE DURATION OF DAYTIME ILLUMINATION Journal article Belgorod Belgorod State Technological University named after V.G. Shukhov 2022 7 с. Journal article local Korkina E. V. Shmarov I. A. Voytovich Elena Valerievna bulletinbstu.editorum.ru