LEHTINEN, T. Ruben Erik Nirvi 1905–86. Finnisch-Ugrische Forschungen, [S. l.], v. 1987, n. 48, p. 121–125, 1987. DOI: 10.33339/fuf.110501. Disponível em: https://journal.fi/fuf/article/view/110501. Acesso em: 21 nov. 2024.