BIERNIAWSKI, A.; GROCHOWSKI, B. O Kształtowaniu Kratownic na Minimum Potencjału. Engineering Transactions, [S. l.], v. 8, n. 1, p. 139–165, 1960. Disponível em: https://et3.ippt.pan.pl/index.php/et/article/view/2915. Acesso em: 9 jun. 2025.