@article{JMAG_2004_11_2_a3,
     author = {N. A. Lyul'ko},
     title = {Increasing of smoothness of the solutions to a boundary value problem for the wave equation on the plane},
     journal = {\v{Z}urnal matemati\v{c}eskoj fiziki, analiza, geometrii},
     pages = {169--176},
     year = {2004},
     volume = {11},
     number = {2},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/JMAG_2004_11_2_a3/}
}