<https://secure.gravatar.com/avatar/12e6de2bed9c0c1e684c4507f3321257?s=96&amp;d=mm&amp;r=g>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://raysupreme.com/how-to-think-like-leonardo-da-vinci-summary-in-english/>