| smo | <http://crossforest.eu/measures/ontology/> |
| unit | <http://crossforest.eu/measures/data/unit> |
| owl | <http://www.w3.org/2002/07/owl> |
| rdf | <http://www.w3.org/1999/02/22-rdf-syntax-ns> |
| xml | <http://www.w3.org/XML/1998/namespace> |
| xsd | <http://www.w3.org/2001/XMLSchema> |
| rdfs | <http://www.w3.org/2000/01/rdf-schema> |
| vann | <http://purl.org/vocab/vann> |
| dc | <http://purl.org/dc/elements/1.1> |