PUST, H.-C. London Underground Map. WLBforum, Stuttgart, v. 21, n. 1, p. 40–41, 2019. DOI: 10.53458/wlbf.v21i1.133. Disponível em: https://journals.wlb-stuttgart.de/ojs/index.php/wlbf/article/view/133. Acesso em: 19 apr. 2024.