Abel, Andrea. “A Trilingual Learner Corpus Illustrating European Reference Levels”. RiCOGNIZIONI. Rivista di Lingue e Letterature straniere e Culture moderne 1, no. 2 (December 30, 2014): 111–126. Accessed April 19, 2025. https://ojsunito33.archicoop.it/index.php/ricognizioni/article/view/702.