@article{IM2_1982_18_2_a2,
     author = {B. M. Levitan},
     title = {Almost periodicity of infinite-zone potentials},
     journal = {Izvestiya. Mathematics },
     pages = {249--273},
     publisher = {mathdoc},
     volume = {18},
     number = {2},
     year = {1982},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/IM2_1982_18_2_a2/}
}