Update README.md

README.md

@@ -50,5 +50,14 @@ Numbers in parentheses denote absolute gains over the single-agent baseline.
 | Overall | Average | **38.33** |
 
 ## Citation
-
-Coming soon.
+```
+@misc{zhang2026metaagentxbreakingceiling,
+      title={MetaAgent-X : Breaking the Ceiling of Automatic Multi-Agent Systems via End-to-End Reinforcement Learning}, 
+      author={Yaolun Zhang and Yujie Zhao and Nan Wang and Yiran Wu and Jiayu Chang and Yizhao Chen and Qingyun Wu and Jishen Zhao and Huazheng Wang},
+      year={2026},
+      eprint={2605.14212},
+      archivePrefix={arXiv},
+      primaryClass={cs.AI},
+      url={https://arxiv.org/abs/2605.14212}, 
+}
+```