Ricardo Avila and  Gabriel Lopes and  Vania Vidal and  Jose Macedo,  Using Textual Pre-Processing and Text Mining to Create Semantic Links.   journal   = {International Journal of Educational and Pedagogical Sciences}, [online]. World Academy of Science, Engineering and Technology.
    June 2019, vol. 151(7). 947 - 954
    [viewed 19 October 2019]. Available from: https://publications.waset.org/pdf/10010548.