KOBOUROV, Stephen; LANDIS, Matthew. Morphing Planar Graphs in Spherical Space. Journal of Graph Algorithms and Applications, [S. l.], v. 12, n. 1, p. 113–127, 2008. DOI: 10.7155/jgaa.00162. Disponível em: https://jgaa.info/index.php/jgaa/article/view/paper162. Acesso em: 25 dec. 2024.