Graßhoff, Gerd Max Planck Fellow Computational History of Science, Max Planck Institute for the History of Science, Max Planck Society;
https://zenodo.org/record/3577203#.YIkveWhCRTY (Any fulltext)
Graßhoff, G., & Kotschka, F. (2019). Ancient Conical Sundial Measurements. Zenodo. doi:10.5281/zenodo.3577203.