@article{MZM_2012_91_4_a16,
     author = {V. A. Mikhailets and V. M. Molyboga},
     title = {On the {Spectrum} of {Singular} {Perturbations} of {Operators} on the {Circle}},
     journal = {Matemati\v{c}eskie zametki},
     pages = {629--632},
     publisher = {mathdoc},
     volume = {91},
     number = {4},
     year = {2012},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_2012_91_4_a16/}
}