Ichihan Tai and  Bill Olson and  Paul Blessner,  Unsupervised Text Mining Approach to Early Warning System.   journal   = {International Journal of Computer and Information Engineering}, [online]. World Academy of Science, Engineering and Technology.
    March 2016, vol. 112(4). 788 - 793
    [viewed 19 April 2024]. Available from: https://publications.waset.org/pdf/10004327.