Clas Thunberg (left) and Ossi Blomqvist at the 1931 World Speedskating Championships in Helsinki
Unknown author<span style="display: none;">Unknown author</span>
<a rel="nofollow" class="external free" href="https://audiovis.nac.gov.pl/obraz/195845/">https://audiovis.nac.gov.pl/obraz/195845/</a>