Akhmad Dzulfiqar Ilyas (2023) “The Use of Duolingo Application to Improve Students’ Vocabulary Size at University Level”, Vidhyayana - An International Multidisciplinary Peer-Reviewed E-Journal - ISSN 2454-8596, 8(4). Available at: https://vidhyayanaejournal.org/journal/article/view/620 (Accessed: 23 November 2024).