1. Ahonen, H., Heinonen, O., Klemettinen, M., Verkamo, A.I.: Applying data mining techniques in text analysis. Tech Report C-1997-23, University of Helsinki, Department of Computer Science (1997)
2. Mannila, H., Toivonen, H.: Discovering generalized episodes using minimal occurrences. In: Proceedings of the Second International Conference on Knowledge Discovery and Data Mining (KDD 1996), Portland, Oregon, pp. 146–151. AAAI Press, Menlo Park (1996)
3. Mannila, H., Toivonen, H., Verkamo, A.I.: Discovery of frequent episodes in event sequences. Data Mining and Knowledge Discovery 1, 259–289 (1997)
4. Ahonen, H., Heinonen, O., Klemettinen, M., Verkamo, A.I.: Applying data mining techniques for descriptive phrase extraction in digital document collections. In: Proceedings of the Advances in Digital Libraries Conference, p. 2. IEEE Computer Society, Los Alamitos (1998)
5. Besançon, R.a.: Text mining — knowledge extraction from unstructured textual data. In: 6th Conference of International Federation of Classification Societies (IFCS 1998), Rome (1998)