BIRBIRSO, Dereje Tadesse; GERBA, Tesfaye Gudeta. Questioning the Origin of Indo-European: A Comparative Evolutionary Analysis of Hittite and Cushitic (Oromo). International Journal of Sciences: Basic and Applied Research (IJSBAR), Jordan, v. 19, n. 2, p. 250–280, 2015. Disponível em: https://gssrr.org/JournalOfBasicAndApplied/article/view/3181. Acesso em: 16 sep. 2025.