@article{ZNSL_1984_135_a1,
     author = {V. I. Vasyunin},
     title = {A~characterization of finite unions of interpolation sets in terms of solvability of interpolation problems},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {31--35},
     publisher = {mathdoc},
     volume = {135},
     year = {1984},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1984_135_a1/}
}