NESSET, Tore. Chapter 10. Phonology: Pre-Slavic and Common Slavic Vowels and Diphthongs. Septentrio Educational, Tromsø, Norway, n. 1, 2015. DOI: 10.7557/8.3500. Disponível em: https://septentrio.uit.no/index.php/SapEdu/article/view/3500. Acesso em: 27 apr. 2026.