@article{JRAM_1984__347_152595,
     author = {Niels Schwartz},
     title = {Chain signatures and real closures.},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {1--20},
     publisher = {mathdoc},
     volume = {347},
     year = {1984},
     zbl = {0531.12017},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1984__347_152595/}
}