@article{TM_1994_203_a26,
     author = {E. M. Jager and A. Sevink},
     title = {A~prolongation structure for the nonlinear {Schr\"odinger} equation},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     pages = {292--306},
     publisher = {mathdoc},
     volume = {203},
     year = {1994},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/TM_1994_203_a26/}
}