@article{MZM_2016_99_4_a1,
     author = {A. T. Diab and B. K. Kaldybekova and O. M. Penkin},
     title = {On the {Multiplicity} of {Eigenvalues} of the {Sturm{\textendash}Liouville} {Problem} on {Graphs}},
     journal = {Matemati\v{c}eskie zametki},
     pages = {489--501},
     year = {2016},
     volume = {99},
     number = {4},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_2016_99_4_a1/}
}