KOWALCZYK, Stanisław. PDH Systemy PDH: Sieci WAN nowa poprawka . DEMO, [S. l.], v. 12304, n. 130, 2021. DOI: 10.21641/demo.v12304i130.69. Disponível em: https://ojs.fimagis.pl/demo/article/view/69. Acesso em: 21 may. 2024.