@article{MMO_1955_4_a3,
     author = {B. M. Levitan},
     title = {On the asymptotic behavior of a spectral function and expansion in eigenfunctions of the equation 
},
     journal = {Trudy Moskovskogo matemati\v{c}eskogo ob\^{s}estva},
     pages = {237--290},
     publisher = {mathdoc},
     volume = {4},
     year = {1955},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MMO_1955_4_a3/}
}