Additional Metadata

additionalMetadata
        |___element 'metadata'
              |___element 'unitList'
                    |___element 'unit'
                          |  \___attribute 'id' = 'gramsPerCubicMeter'
                          |  \___attribute 'name' = 'gramsPerCubicMeter'
                          |  \___attribute 'unitType' = 'massDensity'
                          |  \___attribute 'parentSI' = 'kilogramsPerCubicMeter'
                          |  \___attribute 'multiplierToSI' = '0.001'
                          |  \___attribute 'abbreviation' = 'g/m³'
                          |___text 'grams per cubic meter'