T-Rex (Trainable Relation Extraction) is a highly configurable machine learning-based Information Extraction from Text framework, which includes tools for document classification, entity extraction and relation extraction.
D. Roth, and W. tau Yih. HLT-NAACL 2004 Workshop: Eighth Conference on Computational Natural Language Learning (CoNLL-2004), page 1--8. Boston, Massachusetts, USA, Association for Computational Linguistics, (May 2004)