Circular triangle found by Roger Boscovich, with the property that all lines through its vertex bisect its perimeter
<a href="//commons.wikimedia.org/wiki/User:David_Eppstein" class="mw-redirect" title="User:David Eppstein">David Eppstein</a>
<span class="int-own-work" lang="en">Own work</span>, originally published at <a rel="nofollow" class="external free" href="https://11011110.github.io/blog/2021/05/15/linkage.html">https://11011110.github.io/blog/2021/05/15/linkage.html</a>