Freiburg Minster

1. Werner, Heike / Wallner, Mathias (2006): Architektur und Geschichte in Deutschland. Heike Werner Verlag, Munich (Germany), pp. 44-45.
2. Barthel, Rainer / Tutsch, Joram / Kayser, Christian / Jordan, Joseph (2016): Ein bautechnisches Kunstwerk auf dem Prüfstand - Der gotische Turmhelm des Freiburger Münsters. In: Bundesingenieurkammer (2016): Ingenieurbaukunst 2017. Ernst & Sohn, Berlin (Germany), ISBN 9783433031674, pp. 38-45.
3. Barthel, Rainer / Tutsch, Joram / Jordan, Joseph (2016): The Gothic tower of Freiburg Minster, Germany: analysis and repair. In: Proceedings of the Institution of Civil Engineers - Engineering History and Heritage, v. 169, n. 2 (May 2016), pp. 68-83.

   https://doi.org/10.1680/jenhh.16.00001

4. Barthel, Rainer / Tutsch, Joram / Jordan, Joseph (2017): The Gothic Tower of Freiburg Minster, Germany: Analysis and Repair. In: Pelke, Eberhard (2017): Engineering History and Heritage Structures – Viewpoints and Approaches. International Association for Bridge and Structural Engineering (IABSE), Zurich (Switzerland), ISBN 978-3-85748-154-3, pp. 107-112.

   https://doi.org/10.2749/sed015.107

5. Kayser, Christian (2018): Iron on top. The use of wrought iron armatures in the construction of late Gothic openwork spires. Presented at: 6th International Congress on Construction History (6ICCH 2018), July 9-13, 2018, Brussels, Belgium, pp. 795-802.