AL-BAIDHANI, A. K. Sigma model realization in Spinor theory. Amazonia Investiga, [S. l.], v. 8, n. 22, p. 223–228, 2019. Disponível em: https://amazoniainvestiga.info/index.php/amazonia/article/view/309. Acesso em: 22 jul. 2024.