@article{ZNSL_2001_275_a4,
     author = {A. Ya. Kazakov},
     title = {Symmetries of the confluent {Heun} equation},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {55--71},
     publisher = {mathdoc},
     volume = {275},
     year = {2001},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_2001_275_a4/}
}