Bo Xu, Yong Xu, Jiaqing Liang, Chenhao Xie, Bin Liang, Wanyun Cui, and Yanghua Xiao. CN-DBpedia: A Never-Ending Chinese Knowledge Extraction System. In International Conference on Industrial, Engineering and Other Applications of Applied Intelligent Systems, pp. 428-438. Springer, Cham, 2017.
| 中文名 | 上面级 | |
| 作用 | 地球低轨道发射任务 | |
| 通常为 | 第二级或第三级 | |
| 释义 | 多级火箭的第一级以上 |
| 标签 | 科学 |