ROSE, H. E. Ternary Recursive Arithmetic. MATHEMATICA SCANDINAVICA, [S. l.], v. 10, p. 201–216, 1962. DOI: 10.7146/math.scand.a-10528. Disponível em: https://www.mscand.dk/article/view/10528. Acesso em: 5 may. 2024.