OLSEN, Helge. Gymnastikminder. Forum for Idræt, [S. l.], v. 3, n. 1, 1987. DOI: 10.7146/ffi.v3i0.31907. Disponível em: https://tidsskrift.dk/forumforidraet/article/view/31907. Acesso em: 6 dec. 2025.