@article{ZNSL_2021_506_a2,
     author = {V. M. Babich},
     title = {Space-time ray method for whispering gallery waves},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {15--20},
     publisher = {mathdoc},
     volume = {506},
     year = {2021},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_2021_506_a2/}
}