Schematic of the ignition of the motor of a <a href="https://en.wikipedia.org/wiki/Citro%C3%ABn_2CV" class="extiw" title="en:Citroën 2CV">Citroën 2CV</a> and its derivatives.
<a href="//commons.wikimedia.org/w/index.php?title=User:Ruizo&amp;action=edit&amp;redlink=1" class="new" title="User:Ruizo (page does not exist)">Ruizo</a>
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<span class="int-own-work" lang="en">Own work</span>