Biphasic Sleep Pie Chart
<ul><li><a href="//commons.wikimedia.org/wiki/File:Biphasic.png" title="File:Biphasic.png">Biphasic.png</a>: <a href="//commons.wikimedia.org/w/index.php?title=User:Jorel314&amp;action=edit&amp;redlink=1" class="new" title="User:Jorel314 (page does not exist)">Jorel314</a></li>
<li>derivative work: <a href="//commons.wikimedia.org/wiki/User:Master_Uegly" title="User:Master Uegly">Master Uegly</a> (<a href="//commons.wikimedia.org/wiki/User_talk:Master_Uegly" title="User talk:Master Uegly"><span class="signature-talk">talk</span></a>)</li></ul>
<ul><li><a href="//commons.wikimedia.org/wiki/File:Biphasic.png" title="File:Biphasic.png">Biphasic.png</a></li></ul>