LEI, Xinyun; LIU, Siqi. Has Barack Obama Changed his Language in Later Life? A Case Study of -ing/-in Variation and the MOUTH Vowel. Lifespans and Styles, [S. l.], v. 2, n. 2, p. 2–9, 2016. DOI: 10.2218/ls.v2i2.2016.1608. Disponível em: https://journals.ed.ac.uk/lifespansstyles/article/view/1608. Acesso em: 3 jul. 2024.