@article{IM2_2003_67_4_a5,
     author = {S. P. Khekalo},
     title = {Iso-Huygens deformations of the {Cayley} operator by the general {Lagnese{\textendash}Stellmacher} potential},
     journal = {Izvestiya. Mathematics},
     pages = {815--836},
     year = {2003},
     volume = {67},
     number = {4},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/IM2_2003_67_4_a5/}
}