@article{DOCMA_2004__9__a14,
     author = {Ancona, A. and Helffer, B. and Hoffmann-Ostenhof, T.},
     title = {Nodal domain theorems \`a la {Courant}},
     journal = {Documenta mathematica},
     pages = {283--299},
     publisher = {mathdoc},
     volume = {9},
     year = {2004},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/DOCMA_2004__9__a14/}
}