update paper link and citation

README.md

@@ -109,24 +109,11 @@ Mixed-integer convex programming is an active area of research, and we are seeki
 
 ## References
 
-If you find Pajarito useful in your work, we kindly request that you cite the following [paper](http://dx.doi.org/10.1007/978-3-319-33461-5_9) ([arXiv preprint](http://arxiv.org/abs/1511.06710)):
-
-    @Inbook{LubinYamangilBentVielma2016,
-    author="Lubin, Miles
-    and Yamangil, Emre
-    and Bent, Russell
-    and Vielma, Juan Pablo",
-    editor="Louveaux, Quentin
-    and Skutella, Martin",
-    title="Extended Formulations in Mixed-Integer Convex Programming",
-    bookTitle="Integer Programming and Combinatorial Optimization: 18th International Conference, IPCO 2016, Li{\`e}ge, Belgium, June 1-3, 2016, Proceedings",
-    year="2016",
-    publisher="Springer International Publishing",
-    address="Cham",
-    pages="102--113",
-    isbn="978-3-319-33461-5",
-    doi="10.1007/978-3-319-33461-5_9",
-    url="http://dx.doi.org/10.1007/978-3-319-33461-5_9"
-    }
+If you find Pajarito useful in your work, we kindly request that you cite the following paper ([arXiv preprint](http://arxiv.org/abs/1808.05290)), which is recommended reading for advanced users:
 
-The paper describes the motivation of Pajarito and is recommended reading for advanced users.
+    @article{CoeyLubinVielma2018,
+      title={Outer approximation with conic certificates for mixed-integer convex problems},
+      author={Coey, Chris and Lubin, Miles and Vielma, Juan Pablo},
+      journal={arXiv preprint arXiv:1808.05290},
+      year={2018}
+    }