NOWAK, S. Wittgenstein 1929-1930 – the Color Exclusion Problem (in Polish). Diametros, [S. l.], n. 43, p. 118–136, 2015. DOI: 10.13153/diam.43.2015.720. Disponível em: https://diametros.uj.edu.pl/diametros/article/view/720. Acesso em: 16 jan. 2022.