LEHTO, O. Studying the cognitive states of animals: Epistemology, ethology and ethics. Sign Systems Studies, [S. l.], v. 37, n. 3/4, p. 369–422, 2009. DOI: 10.12697/SSS.2009.37.3-4.02. Disponível em: https://ojs.utlib.ee/index.php/sss/article/view/SSS.2009.37.3-4.02. Acesso em: 25 apr. 2024.