<https://secure.gravatar.com/avatar/827dce92412d53d4c913d5547b701cb6?d=mm&r=g>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<http://schema.org/ImageObject>
<https://opinionduel.com/informatica/diferencia-entre-ejb-2-1-y-ejb-3-0/>