@article{DAN_1981_258_3_a4,
     author = {M. G. Krein and G. K. Langer},
     title = {Continual analogues of orthogonal polynomials on the unit circle with respect to an indefinite weight, and the extension problems connected with them},
     journal = {Doklady Akademii Nauk},
     pages = {537--541},
     publisher = {mathdoc},
     volume = {258},
     number = {3},
     year = {1981},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1981_258_3_a4/}
}