Leo Determan (r) and Rudy den Outer in the FD H125 on the Kralingsche Plas (NED) in 1970 (Note the dredging equipment used from 1969 - 1971)
<a href="//commons.wikimedia.org/wiki/User:NED33" title="User:NED33">NED33</a>
CC BY-SA 4.0
<span class="int-own-work" lang="en">Own work</span>