THE PORTAL CRANES WITH TANDEM SPREADERS AND THEIR COST ADVANTAGES. Perner’s Contacts, [S. l.], v. 6, n. 1, p. 349–358, 2011. Disponível em: https://ojs-demo.upce.cz/index.php/perner/article/view/809. Acesso em: 2 mar. 2026.