@article{ZNSL_2001_276_a1,
     author = {E. P. Golubeva},
     title = {On spectrum {L\'evy} constants for quadratic irrationalities and class numbers of real quadratic fields},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {20--40},
     publisher = {mathdoc},
     volume = {276},
     year = {2001},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_2001_276_a1/}
}