Caspar C.27 photo from L'Air March 15,1926
L'Air magazine
1926-03-15
<a rel="nofollow" class="external free" href="https://gallica.bnf.fr/ark:/12148/bpt6k98044204/f17.double">https://gallica.bnf.fr/ark:/12148/bpt6k98044204/f17.double</a>