@article{ZNSL_1998_254_a1,
     author = {E. P. Golubeva},
     title = {Geodesics on the upper half-plane and distribution of quadratic irrationalities},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {28--55},
     publisher = {mathdoc},
     volume = {254},
     year = {1998},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1998_254_a1/}
}