@article{FAA_1992_26_4_a13,
     author = {V. N. Karpushkin},
     title = {Bounds for the {Betti} numbers of a level surface of a harmonic polynomial},
     journal = {Funkcionalʹnyj analiz i ego prilo\v{z}eni\^a},
     pages = {86--88},
     publisher = {mathdoc},
     volume = {26},
     number = {4},
     year = {1992},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/FAA_1992_26_4_a13/}
}