@article{SIGMA_2007_3_a18,
     author = {Valentyn Tychynin and Olga Petrova and Olesya Tertyshnyk},
     title = {Nonlocal {Symmetries} and {Generation} of {Solutions} for {Partial} {Differential} {Equations}},
     journal = {Symmetry, integrability and geometry: methods and applications},
     year = {2007},
     volume = {3},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SIGMA_2007_3_a18/}
}