@article{MZ_1965__87_170375,
     author = {Helmut Salzmann and Herbert Busemann},
     title = {Metric collineations and inverse problems.},
     journal = {Mathematische Zeitschrift},
     pages = {214--240},
     publisher = {mathdoc},
     volume = {87},
     year = {1965},
     zbl = {0125.11102},
     url = {http://geodesic.mathdoc.fr/item/MZ_1965__87_170375/}
}