@article{NUMA_1980__34_132657,
     author = {J. Sprekels},
     title = {Exact {Bounds} for the {Solution} {Branches} of {Nonlinear} {Eigenvalue} {Problems.}},
     journal = {Numerische Mathematik},
     pages = {29--40},
     publisher = {mathdoc},
     volume = {34},
     year = {1980},
     zbl = {0403.65023},
     url = {http://geodesic.mathdoc.fr/item/NUMA_1980__34_132657/}
}