@article{JEMS_2015_17_11_a2,
     author = {Giulio Ciraolo and Rolando Magnanini and Shigeru Sakaguchi},
     title = {Symmetry of minimizers with a level surface parallel to the boundary},
     journal = {Journal of the European Mathematical Society},
     pages = {2789--2804},
     publisher = {mathdoc},
     volume = {17},
     number = {11},
     year = {2015},
     doi = {10.4171/jems/571},
     url = {http://geodesic.mathdoc.fr/articles/10.4171/jems/571/}
}