<https://webartdevelopers.com/blog/bootstrap-4-alert-messages-with-dismiss-and-continue-button/#contactpoint>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<http://schema.org/ContactPoint>
<https://webartdevelopers.com/blog/bootstrap-4-alert-messages-with-dismiss-and-continue-button/>