DIN 2137-11-2003 文本和办公设备.键盘.第11部分:数据和文本加工以及打字机用德文键盘.字符键或功能键的分配及键上符号布局的管理原理
Text and office systems - Keyboards - Part 11: German keyboard for data and text processing as well as for typewriters; Principles governing the allocation of characters or functions to keys and the placement of their symbols on the keys