. . . . "The task is not formulated as a classification one, but we argue it is relevant for the completeness of the extracted facts: rather, it is carried out via matching and transformation rule pairs. Given for instance the input expression tra il 1920 e il 1925 (between 1920 and 1925), our normalizer first matches it through a regular expression rule, then applies a transformation rule complying to the XML Schema Datatypes 20 (typically dates and times) standard, and finally produces the following output: 21" . . . . "2019-11-10T18:05:11+01:00"^^ . .