@article{UZERU_1990_3_a6,
     author = {S. V. Sarkissian},
     title = {On the vibration of nonhomogeneous string},
     journal = {Proceedings of the Yerevan State University. Physical and mathematical sciences},
     pages = {41--44},
     publisher = {mathdoc},
     number = {3},
     year = {1990},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/UZERU_1990_3_a6/}
}