<https://ivyweb.net/tag/%e0%b8%97%e0%b8%b2%e0%b8%87%e0%b9%80%e0%b8%82%e0%b9%89%e0%b8%b2%e0%b9%80%e0%b8%a5%e0%b9%88%e0%b8%99-pg-slot/#breadcrumb>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
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