fixed citation

README.md

@@ -42,11 +42,11 @@ result = qa_pipe(question=text,context=context)
  
  # If you used this model please cite us as :
  ```
-@misc{antoun2020aragpt2,
-      title={AraGPT2: Pre-Trained Transformer for Arabic Language Generation},
+@misc{antoun2020araelectra,
+      title={AraELECTRA: Pre-Training Text Discriminators for Arabic Language Understanding},
       author={Wissam Antoun and Fady Baly and Hazem Hajj},
       year={2020},
-      eprint={2012.15520},
+      eprint={2012.15516},
       archivePrefix={arXiv},
       primaryClass={cs.CL}
 }