HAGEN, Rolf. Contracture of the Quadriceps Muscle in Children: A Report of 12 Cases. Acta Orthopaedica, [S. l.], v. 39, n. 4, p. 565–578, 1968. DOI: 10.3109/17453676808989671. Disponível em: https://actaorthop.org/actao/article/view/30115. Acesso em: 20 may. 2026.