@article{10_5817_AM2014_1_21,
     author = {Vondra, Jan},
     title = {Natural transformations of connections on the first principal prolongation},
     journal = {Archivum mathematicum},
     pages = {21--25},
     publisher = {mathdoc},
     volume = {50},
     number = {1},
     year = {2014},
     doi = {10.5817/AM2014-1-21},
     mrnumber = {3194765},
     zbl = {06391562},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.5817/AM2014-1-21/}
}