HUFFMAN, D. P.; PATTERSON, T. The Design of Gray Earth: A Monochrome Terrain Dataset of the World. Cartographic Perspectives, [S. l.], n. 74, p. 61–70, 2013. DOI: 10.14714/CP74.580. Disponível em: https://cartographicperspectives.org/index.php/journal/article/view/cp74-huffman-patterson. Acesso em: 25 apr. 2024.