Investigating transportation research based on social media analysis: a systematic mapping review. - Tasnim M. A. Zayet; Maizatul Akmar Ismail 001; Kasturi Dewi Varathan; Rafidah M. D. Noor; Hui Na Chua; Angela Lee; Yeh Ching Low; Sheena Kaur Jaswant Singh (Scientometrics, 2021)