Opérations dans les constructions acycliques
Séminaire Henri Cartan, Volume 7 (1954-1955) no. 1, Talk no. 6, 11 p. 
@article{SHC_1954-1955__7_1_A6_0,
     author = {Cartan, Henri},
     title = {Op\'erations dans les constructions acycliques},
     journal = {S\'eminaire Henri Cartan},
     publisher = {Secr\'etariat math\'ematique},
     volume = {7},
     number = {1},
     year = {1954-1955},
     note = {talk:6},
     language = {fr},
     url = {http://www.numdam.org/item/SHC_1954-1955__7_1_A6_0}
}

Cartan, H. Opérations dans les constructions acycliques. Séminaire Henri Cartan, Volume 7 (1954-1955) no. 1, Talk no. 6, 11 p. http://www.numdam.org/item/SHC_1954-1955__7_1_A6_0/