@article{MZ_1980__173_172969,
     author = {David L. Ragozin},
     title = {Curvatures and {Curves} in {Hilbert} {Space.}},
     journal = {Mathematische Zeitschrift},
     pages = {51--68},
     publisher = {mathdoc},
     volume = {173},
     year = {1980},
     zbl = {0417.53004},
     url = {http://geodesic.mathdoc.fr/item/MZ_1980__173_172969/}
}