FIRLEJ, S. Design, construction and control of a spherical rolling robot with internal two-wheel cart. Automatyka/Automatics, [S. l.], v. 19, n. 2, p. 63, 2017. DOI: 10.7494/automat.2015.19.2.63. Disponível em: https://journals.agh.edu.pl/automat/article/view/2603. Acesso em: 2 may. 2024.