@article{ELMA_1987__42_4_141394,
     author = {Walter Benz},
     title = {An elementary proof of the {Theorem} of {Beckmann} and {Quarles.}},
     journal = {Elemente der Mathematik},
     pages = {4--9},
     publisher = {mathdoc},
     volume = {42},
     number = {4},
     year = {1987},
     zbl = {0701.51013},
     url = {http://geodesic.mathdoc.fr/item/ELMA_1987__42_4_141394/}
}