@article{SM_1991_70_2_a5,
     author = {V. A. Zolotarev},
     title = {Time cones and a~functional model on {a~Riemann} surface},
     journal = {Sbornik. Mathematics},
     pages = {399--429},
     publisher = {mathdoc},
     volume = {70},
     number = {2},
     year = {1991},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_1991_70_2_a5/}
}