FISCHER-JØRGENSEN, E. Auditory Investigation of German Tense and Lax Vowels . Annual Report of the Institute of Phonetics University of Copenhagen, [S. l.], v. 1, p. 91–92, 1967. DOI: 10.7146/aripuc.v1i.130585. Disponível em: https://tidsskrift.dk/ARIPUC/article/view/130585. Acesso em: 4 may. 2024.