00537naa#a2200193#i#450# EN\\bibl\101885 20250901060439.1 2588-0209 20201225b2020####ek#y0engy0150####ca RU JUSTIFICATION OF THE EFFECTIVENESS OF POLYGONAL PROFILE CHANNELS MADE OF PRECAST L-SHAPED REINFORCED CONCRETE BLOCKS Journal article Moscow Electronic science 2020 0 с. Journal article local mshj.ru