Update README.md

README.md

@@ -99,11 +99,13 @@ Ahmed Abdelali, Sabit Hassan, Hamdy Mubarak, Kareem Darwish and Younes Samih
 
 ## Reference
 ```
-@article{abdelali2020qarib,
-  title={QARiB: QCRI Arabic and Dialectal BERT},
-  author={Ahmed, Abdelali and Sabit, Hassan and Hamdy, Mubarak and Kareem, Darwish and Younes, Samih},
-  link={https://github.com/qcri/QARIB},
-  year={2020}
+@article{abdelali2021pretraining,
+    title={Pre-Training BERT on Arabic Tweets: Practical Considerations},
+    author={Ahmed Abdelali and Sabit Hassan and Hamdy Mubarak and Kareem Darwish and Younes Samih},
+    year={2021},
+    eprint={2102.10684},
+    archivePrefix={arXiv},
+    primaryClass={cs.CL}
 }
 ```