Tenschert, Ruth, Leander Pallas, Sebastian Kempgen, and Paul Bellendorf. “Eternal Witnesses: Documentation and Analysis of Carved Historic Graffiti and Inscriptions on Stone Surfaces”. goINDIGO (September 6, 2024): 147–162. Accessed October 30, 2025. https://www.journals.wisethorough.com/index.php/indigo/article/view/980.