@article{SE_1963__5__A1_0,
     author = {Ver Eecke, Paul},
     title = {Sur les connexions d'\'el\'ements de contact},
     journal = {S\'eminaire Ehresmann. Topologie et g\'eom\'etrie diff\'erentielle},
     note = {talk:1},
     pages = {i-vii,1-70},
     publisher = {Secr\'etariat math\'ematique},
     volume = {5},
     year = {1963},
     language = {fr},
     url = {http://www.numdam.org/item/SE_1963__5__A1_0/}
}