@article{MZ_1978__158_172614,
     author = {Jochen Br\"uning},
     title = {\"Uber {Knoten} von {Eigenfunktionen} des {Laplace-Beltrami-Operators.}},
     journal = {Mathematische Zeitschrift},
     pages = {15--22},
     publisher = {mathdoc},
     volume = {158},
     year = {1978},
     url = {http://geodesic.mathdoc.fr/item/MZ_1978__158_172614/}
}