@article{CC_2003_32_3_a5,
     author = {Dambrine, M. and Soko{\l}owski, J. and \.Zochowski, A.},
     title = {On stability analysis in shape optimization: critical shapes for {Neumann} poblem},
     journal = {Control and Cybernetics},
     pages = {503--528},
     publisher = {mathdoc},
     volume = {32},
     number = {3},
     year = {2003},
     zbl = {1126.49034},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CC_2003_32_3_a5/}
}