<https://www.codeproject.com/Articles/5282980/Fastest-Fulltext-Vector-Scalar-Exact-Searcher>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://codeproject.freetls.fastly.net/Articles/5282980/Fastest-Fulltext-Vector-Scalar-Exact-Searcher?msg=5757380>