@article{MAN_1979__240_163244,
     author = {Willi J\"ager and Helmut Kaul},
     title = {Uniqueness of {Harmonie} {Mappings} and of {Solutions} of {Elliptic} {Equations} on {Riemannnian} {Manifolds.}},
     journal = {Mathematische Annalen},
     pages = {231--250},
     publisher = {mathdoc},
     volume = {240},
     year = {1979},
     zbl = {0388.58002},
     url = {http://geodesic.mathdoc.fr/item/MAN_1979__240_163244/}
}