@article{10_1090_S0894_0347_1990_1035413_2,
     author = {Donnelly, Harold and Fefferman, Charles},
     title = {Nodal sets for eigenfunctions of the {Laplacian} on surfaces},
     journal = {Journal of the American Mathematical Society},
     pages = {333--353},
     publisher = {mathdoc},
     volume = {03},
     number = {2},
     year = {1990},
     doi = {10.1090/S0894-0347-1990-1035413-2},
     url = {http://geodesic.mathdoc.fr/articles/10.1090/S0894-0347-1990-1035413-2/}
}