* {@link UnitDefinition#areIdentical(UnitDefinition, UnitDefinition)}
* in comparison to the given {@link UnitDefinition}, or
* {@code null} if no such element can be found.
*/
public UnitDefinition findIdentical(UnitDefinition unitDefinition) {
return getListOfUnitDefinitions().firstHit(new IdenticalUnitDefinitionFilter(unitDefinition));
}