NGHIÊM, H. . Problems in General K-Theory. Mathematical Statistician and Engineering Applications, [S. l.], v. 70, n. 2, p. 120–132, 2021. DOI: 10.17762/msea.v70i2.20. Disponível em: https://www.philstat.org/index.php/MSEA/article/view/20. Acesso em: 16 apr. 2024.