DIN EN 81346-2:2010-03 工业系统、设施、设备和工业产品.结构原则和基准标识.第2部分:物体分类和分类代码(IEC 81346-2-2009).德文版本EN 81346-2-2009
Industrial systems, installations and equipment and industrial products - Structuring principles and reference designations - Part 2: Classification of objects and codes for classes (IEC 81346-2:2009); German version EN 81346-2:2009