airmail stamp series “wooden dove”
<a href="https://de.wikipedia.org/wiki/Ernst_Aufseeser" class="extiw" title="de:Ernst Aufseeser">de:Ernst Aufseeser</a> (1880-1940). scanned by <a href="//commons.wikimedia.org/wiki/User:NobbiP" title="User:NobbiP">NobbiP</a>
scanned by <a href="//commons.wikimedia.org/wiki/User:NobbiP" title="User:NobbiP">NobbiP</a>