<https://www.advancedsciencenews.com/optical-spectroscopy-reveals-biexcitons-monolayer-tungstenite/#article>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://www.advancedsciencenews.com/optical-spectroscopy-reveals-biexcitons-monolayer-tungstenite/>