add citation to readme

README.md

@@ -51,6 +51,23 @@ Atlas uses a fast, scalable edge decomposition to split graphs into graph layers
 For the edge decomposition algorithm, go to [github.com/fredhohman/atlas-algorithm][atlas-algorithm].
 
 
+## Citation
+
+**Atlas: Local Graph Exploration in a Global Context**. 
+James Abello*, Fred Hohman*, Varun Bezzam, Duen Horng (Polo) Chau 
+ACM Conference on Intelligent User Interfaces (IUI). Los Angeles, CA, USA, 2019. 
+* Authors contributed equally.
+
+```
+@inproceedings{hohman2019atlas,
+ title={Atlas: Local Graph Exploration in a Global Context},
+ author={Abello, James and Hohman, Fred and Bezzam, Varun and Chau, Duen Horng},
+ booktitle={Proceedings of the International Conference on Intelligent User Interfaces},
+ year={2019},
+ organization={ACM}
+}
+```
+
 ## License
 
 MIT License. See [`LICENSE.md`](LICENSE.md).