<a href="https://en.wikipedia.org/wiki/Roger_Penrose" class="extiw" title="en:Roger Penrose">Roger Penrose</a> at a conference who is showing something at an <i>(blurred due to copyright!)</i> etching of <a href="https://en.wikipedia.org/wiki/M._C._Escher" class="extiw" title="en:M. C. Escher">Maurits Cornelis Escher</a>  <a rel="nofollow" class="external text" href="http://procsilas.net/?p=14">procsilas.net/?p=14</a>
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<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/47207654@N00/272485906/">capturing infinity</a>