<https://concertpostergallery.com/blogs/news/how-to-sell-your-vintage-concert-posters-for-top-dollar-in-24-hours>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://psychedelicart.com/blogs/news/how-to-sell-your-vintage-concert-posters-for-top-dollar-in-24-hours>