<https://secure.gravatar.com/avatar/94ed20f847800611baaf7680333f54ea?s=96&amp;d=mm&amp;r=g>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://artigos.etc.br/educacao-ead-uma-visao-inovadora.html>