@article{AraujoLMP20,
  author    = {Lourdes Araujo and
               Fernando L{\'{o}}pez{-}Ostenero and
               Juan Mart{\'{\i}}nez{-}Romo and
               Laura Plaza},
  title     = {Deep-Learning Approach to Educational Text Mining and Application
               to the Analysis of Topics' Difficulty},
  journal   = {{IEEE} Access},
  volume    = {8},
  pages     = {218002--218014},
  year      = {2020},
}