@article{RM_1998_53_1_a6,
     author = {Yu. Yu. Berest and A. P. Veselov},
     title = {On the singularities of potentials of exactly soluble  {Schr\"odinger} equations and on {Hadamard's} problem},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     pages = {208--209},
     publisher = {mathdoc},
     volume = {53},
     number = {1},
     year = {1998},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/RM_1998_53_1_a6/}
}