VAN DER WAALS, J. Discontinuity, cultural evolution and the historic event. Proceedings of the Society of Antiquaries of Scotland, [S. l.], v. 114, p. 1–14, 1985. DOI: 10.9750/PSAS.114.1.14. Disponível em: https://journals.socantscot.org/index.php/psas/article/view/9152. Acesso em: 18 apr. 2024.