@article{MZ_1972__125_171697,
     author = {Oldrich Kowalski},
     title = {On {Regular} {Curvature} {Structures.}},
     journal = {Mathematische Zeitschrift},
     pages = {129--138},
     publisher = {mathdoc},
     volume = {125},
     year = {1972},
     zbl = {0234.53024},
     url = {http://geodesic.mathdoc.fr/item/MZ_1972__125_171697/}
}