i><a href="https://en.wikipedia.org/wiki/Graphite">Graphite - Wikipedia</a></li>
<li><a href="https://en.wikipedia.org/wiki/Graphene">Graphene- Wikipedia</a></li>
<li><a href="https://en.wikipedia.org/wiki/Pyrolytic_carbon">Pyrolytic carbon - Wikipedia</a></li>
<li><a href="http://www.ioffe.ru/SVA/NSM/Semicond/Diamond">Diamond - NSM Archive</a></li>
<li><a href="http://www.diamond-materials.de/propopt_en.htm">CVD Diamond - Diamond Materials</a></li>
<li><a href="https://www.webelements.com/carbon/">Carbon -