@article{IM2_2006_70_4_a0,
     author = {A. N. Bakhvalov},
     title = {On local behaviour of multi-dimensional harmonic variation},
     journal = {Izvestiya. Mathematics },
     pages = {641--660},
     publisher = {mathdoc},
     volume = {70},
     number = {4},
     year = {2006},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/IM2_2006_70_4_a0/}
}