KNAUER, Nicolai. Die Grafenburg Lauffen am Neckar. Zeitschrift des Zabergäuvereins, [S. l.], n. 3-4, p. 1–24, 2007. DOI: 10.53458/r4fx7t91. Disponível em: https://journals.wlb-stuttgart.de/index.php/zz/article/view/19390. Acesso em: 11 mar. 2026.