an Entity references as follows:
An instance of this class is an actual float value for a quantitative property of a product. This instance is usually characterized by a minimal value, a maximal value, and a unit of measurement. This class is a work-around caused by the fact that OWL does only support binary relations, and that datatype ranges cannot be easily handled in OWL. Examples: The intervals "between 10.0 and 25.4 kilogramms" or "10.2 and 15.5 milimeters".