Rhythms and fluctuations of culture. Letras, Lima, Peru, v. 5, n. 12, p. 50–78, 1939. DOI: 10.30920/letras.5.12.3. Disponível em: https://revistaletras.unmsm.edu.pe/index.php/le/article/view/1060. Acesso em: 13 sep. 2026.