@article{MZ_1978__159_172650,
     author = {Daniel Lehmann and Claude Albert},
     title = {Une alg\`ebre gradu\'ee universelle pour les connexions sans torsion.},
     journal = {Mathematische Zeitschrift},
     pages = {133--142},
     publisher = {mathdoc},
     volume = {159},
     year = {1978},
     zbl = {0359.58002},
     url = {http://geodesic.mathdoc.fr/item/MZ_1978__159_172650/}
}