00544naa#a2200181#i#450# EN\\bibl\14222 /en/manage/index 20250211194659.2 1999-8775 20150930b2015####ek#y0engy0150####ca RUS RU Periodic vibrations of nongomogeneous string with clamped and free ends. Journal article Bryansk Bryansk State Technical University 2015 9 с. Journal article local Rudakov Igor fht.editorum.ru /en/manage/index