Update README.md

Author: cgnorthcutt

README.md

@@ -4,6 +4,23 @@
 
 The cleaned and corrected test sets for all ten ML benchmark test sets, along with the indices for all label errors at https://labelerrors.com will be made available here on April 21.
 
+## Citation for the paper
+
+```
+@misc{northcutt2021labelerrors,
+      title={Pervasive Label Errors in Test Sets Destabilize Machine Learning Benchmarks}, 
+      author={Curtis G. Northcutt and Anish Athalye and Jonas Mueller},
+      year={2021},
+      eprint={2103.14749},
+      archivePrefix={arXiv},
+      primaryClass={stat.ML}
+}
+```
+
+On arXiv: https://arxiv.org/pdf/2103.14749.pdf
+
+Preliminary versions of this work were accepted to NeurIPS 2020 (1 workshop) and ICLR 2021 (2 workshops).
+
 ## Selected News Coverage
 
 * [The Register](https://www.theregister.com/2021/04/01/mit_ai_accuracy/)