<https://www.csarmento.uminho.pt/site/api/mapping_markers/635>
<http://omeka.org/s/vocabs/module/mapping#lng>
"1.324395119999997E1"^^<http://www.w3.org/2001/XMLSchema#double>
<https://www.csarmento.uminho.pt/site/s/postal-ilustrado/item/170695>