@article{PM_2009_2009_1_a1,
     author = {Chiacchio, F. },
     title = {Estimates for the first eigenfunction of linear eigenvalue problems via {Steiner} symmetrization.},
     journal = {Publicacions matem\`atiques},
     pages = {47-71},
     publisher = {mathdoc},
     volume = {53},
     number = {1},
     year = {2009},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/PM_2009_2009_1_a1/}
}