SINHA, B. B.; YADAV, R. N. UNIFIED CONTACT STRUCTURE. Tamkang Journal of Mathematics, [S. l.], v. 22, n. 2, p. 125–132, 1991. DOI: 10.5556/j.tkjm.22.1991.4584. Disponível em: https://journals.math.tku.edu.tw/index.php/TKJM/article/view/4584. Acesso em: 4 may. 2024.