@article{SIGMA_2007_3_a54,
     author = {Ivan Kachuryk and Anatoliy Klimyk},
     title = {Eigenfunction {Expansions} of {Functions} {Describing} {Systems} with {Symmetries}},
     journal = {Symmetry, integrability and geometry: methods and applications},
     year = {2007},
     volume = {3},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SIGMA_2007_3_a54/}
}