Witnesses. YAGO is prepared to be extended by new facts.If a new fact was extracted from a particular Web page, we call this page the witness for the fact. We introduce the FoUNDIN relation, which holds between a fact and the URL of the witness page. We use the ExTRACTEDBY relation to identify the technique by which a fact was extracted.The information about witnesses will enable applications to
use, e.g., only facts extracted by a certain technique, facts extracted from a certain source or facts of a certain date