<https://www.edaboard.com/threads/need-of-chemical-filling-compound-for-my-pcb-circuit-reg.399743/>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://www.edaboard.com/threads/need-of-chemical-filling-compound-for-my-pcb-circuit-reg.399743/>