BOLZANO, B. Purely Analytical Proof of a Claim, that Between Each Two Values Resulting in Opposite Signs, There is a Real Equation Element. Annales Universitatis Paedagogicae Cracoviensis | Studia ad Didacticam Mathematicae Pertinentia, [S. l.], v. 9, n. 1, p. 197–217, 2018. Disponível em: https://didacticammath.uken.krakow.pl/article/view/4315. Acesso em: 2 may. 2024.