| 1. | Letter symbols in data sheets for electronic tubes 电子管数据表中的字母符号 |
| 2. | Microwave circuits . letter symbols for characteristics 微波电路.参数文字符号 |
| 3. | Plasma display panels - terminology and letter symbols 等离子体显示板.术语和字母符号 |
| 4. | Letter symbols for discrete semiconductor devices 半导体分立器件文字符号 |
| 5. | Letter symbols for mechanics and time - related phenomena 机械和与时间相关的现象用字母符号 |
| 6. | Nomenclature , definitions , and letter symbols for screw threads 螺纹的字母符号命名和定义 |
| 7. | Graphical and letter symbols for hydrogeology 水文地质学用图形和符号 |
| 8. | Screw threads , nomenclature , definitions , and letter symbols for 螺纹的术语定义和字母符号 |
| 9. | Letter symbols and abbreviations for quantities used in acoustics 声学量值的字母符号和缩写 |
| 10. | Major letter symbols for analytical instrument 分析仪器常用文字符号 |