<http://schema.org/keywords>
"electrical standards, elektrischen Normen, normes \u00E9lectriques, padr\u00F5es el\u00E9tricos"^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.bibliocad.com/library/schematic-of-load-calculaations-in-buildings_43026>