KIRBY, R. S. The Grammar of Graphics. Cartographic Perspectives, [S. l.], n. 40, p. 55–56, 2001. DOI: 10.14714/CP40.597. Disponível em: https://cartographicperspectives.org/index.php/journal/article/view/cp40-kirby. Acesso em: 23 apr. 2024.