@article{BUMI_2009_9_2_1_a13,
     author = {Andr\'e, Yves},
     title = {Ambiguity {Theory,} {Old} and {New}},
     journal = {Bollettino della Unione matematica italiana},
     pages = {259--274},
     publisher = {mathdoc},
     volume = {Ser. 9, 2},
     number = {1},
     year = {2009},
     zbl = {1189.11050},
     mrnumber = {2493655},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/BUMI_2009_9_2_1_a13/}
}