@article{DE_1990_26_9_a27,
     author = {M. V. Fedoryuk},
     title = {Analytic structure of solutions of the {Sturm{\textendash}Liouville} problem with regular singularities},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1648--1650},
     year = {1990},
     volume = {26},
     number = {9},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1990_26_9_a27/}
}