@article{RM_1988_43_5_a30,
     author = {A. V. Sobolev and V. I. Sobolev},
     title = {On~differentiability of {a~Hammerstein} operator and {on~Hammerstein} equations},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     pages = {258--259},
     publisher = {mathdoc},
     volume = {43},
     number = {5},
     year = {1988},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/RM_1988_43_5_a30/}
}