Preparation for classes   in the Gdansk University of Technology Faculty of Ocean Engineering and Ship Technology (Poland)  laboratory
<a href="//commons.wikimedia.org/w/index.php?title=User:Wlitwin&amp;action=edit&amp;redlink=1" class="new" title="User:Wlitwin (page does not exist)">Wojciech Litwin</a>
CC BY 4.0
<span class="int-own-work" lang="en">Own work</span>