@book{MSMF_1965__3__1_0,
     author = {Grillet, P-A.},
     title = {Homomorphismes principaux de tas et de groupo{\"\i}des},
     series = {M\'emoires de la Soci\'et\'e Math\'ematique de France},
     publisher = {Soci\'et\'e math\'ematique de France},
     number = {3},
     year = {1965},
     doi = {10.24033/msmf.3},
     zbl = {0141.01402},
     language = {fr},
     url = {http://www.numdam.org/item/MSMF_1965__3__1_0/}
}