@article{IM2_1991_36_3_a1,
     author = {A. A. Danielyan and B. M. Levitan},
     title = {On the asymptotic behaviour of the {Titchmarsh--Weyl} $m$-function},
     journal = {Izvestiya. Mathematics },
     pages = {487--496},
     publisher = {mathdoc},
     volume = {36},
     number = {3},
     year = {1991},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/IM2_1991_36_3_a1/}
}