@article{KUTGS_1989_19_a7,
     author = {L. M. Kress},
     title = {Affine connections that allow four-term groups of infinitesimal transformations},
     journal = {Trudy Geometricheskogo Seminara},
     pages = {60--70},
     publisher = {mathdoc},
     volume = {19},
     year = {1989},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/KUTGS_1989_19_a7/}
}