PANCHENKO, Dmitri. Solar Light and the Symbolism of the Number Seven. Hyperboreus, Bern, v. 12, p. 21–36, 2007. DOI: 10.36950/hyperboreus.v12a02. Disponível em: https://bop.unibe.ch/Hyperboreus/article/view/13575. Acesso em: 15 may. 2026.