1. Nagata, M. et al.: A newspaper keyword gene- ration method based on key-concept extraction. In: Proceedings of the 37th National Convention Information Processing, pp. 1030–1031 (1988)
2. Morohashi, M.: Automatic indexing survey. Mag. IPS Jpn 25, 918–925 (1984)
3. Lee, S.S., Shishibori, M., Sumitomo, T., Aoe, J.-I.: Extraction of field-coherent passages. Intl. J. Inf. Process. Manage. 38, 173–207 (2002)
4. Al-Hashemi, R.: Text summarization extraction system (TSES) using extracted keywords. Intl. Arab J. e-Technol. 1, 164–168 (2010)
5. Chena, Y.-H., Lub, E.J.-L., Tsaib, M.F.: Finding keywords in blogs: efficient keyword extraction in blog mining via user behaviors. Expert Syst. Appl. 41, 663–670 (2014)