<https://www.ajmc.com/view/copd-is-an-independent-risk-factor-of-colorectal-liver-other-cancers>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://www.ajmc.com/view/copd-is-an-independent-risk-factor-of-colorectal-liver-other-cancers>