@article{JRAM_1993__436_153493,
     author = {Dominikus Noll},
     title = {Second order differentiability of integral functionals on {Sobolev} spaces and {L2-spaces.}},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {1--18},
     publisher = {mathdoc},
     volume = {436},
     year = {1993},
     zbl = {0767.49010},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1993__436_153493/}
}