The article is two years old, and one of the links, the one pointing to https://www.cpepweb.org/cpep_sm_large.html https://www.cpepweb.org/cpep_sm_large.html is

The article is two years old, and one of the links, the one pointing to https://www.cpepweb.org/cpep_sm_large.html https://www.cpepweb.org/cpep_sm_large.html is already dead. Thankfully the internet archive has a backup: http://web.archive.org/web/20200521151158/https://www.cpepweb.org/cpep_sm_large.html http://web.archive.org/web/20200521151158/https://www.cpepwe...