WULFF, R. Volksabstimmungen in Nordeuropa. Folia Scandinavica Posnaniensia, [S. l.], v. 3, p. 67–76, 2007. Disponível em: https://pressto.amu.edu.pl/index.php/fsp/article/view/10933. Acesso em: 7 jun. 2023.