7. December 2018 /

Sulgenbachstollen

<em>Schenker-Wirz, E.: Sulgenbachstollen, 1923-1926 (Hs_1002-0007-035 <a href="http://doi.org/10.3932/ethz-a-000270027">http://doi.org/10.3932/ethz-a-000270027</a>)