Extraction of informations from highly heterogeneous source of textual data

Extracting informations from multiple sources, highly heterogeneous, of textual data and integrating them in order to provide true information is a challenging research topic in the database area. In order to illustrate problems and solutions, one of the most interesting projects facing this problem, TSIMMIS, is presented. Furthermore, a Description Logics approach, able to provide interesting solutions both for data integration and data querying, is introduced.