@article{SD_1960-1961__14_2_A3_0,
     author = {Birkhoff, Garrett},
     title = {Lattice-ordered demigroups},
     journal = {S\'eminaire Dubreil. Alg\`ebre et th\'eorie des nombres},
     note = {talk:19},
     pages = {1--26},
     publisher = {Secr\'etariat math\'ematique},
     volume = {14},
     number = {2},
     year = {1960-1961},
     zbl = {0122.02101},
     language = {en},
     url = {http://www.numdam.org/item/SD_1960-1961__14_2_A3_0/}
}