Pset_SpatialZoneCommon Common properties for Spatial Zones. IfcSpatialZone IfcSpatialZone Reference Reference ID for this specified type in this project (e.g. type 'A-1'), Also referred to as "construction type". It should be provided as an alternative to the name of the "object type", if the software does not support object types and no classification reference to a recognized classification system used. > IFC4.3.0.0 DEPRECATION  The Reference property is deprecated and shall no longer be used, use attribute Name on the relating type instead. Reference 参照 참조 当該プロジェクトで定義する形式の参照ID（例：A-1)、承認された分類に存在しないときに使用される。 해당 프로젝트에 정의된 형식의 참조 ID (예 : A-1) 승인된 분류에 존재하지 않을 때 사용된다. IsExternal Indication whether the element is designed for use in the exterior (TRUE) or not (FALSE). If (TRUE) it is an external element and faces the outside of the building.