correct year in mccan reference for partial ot

Author: rflamary

README.md

@@ -258,7 +258,7 @@ You can also post bug reports and feature requests in Github issues. Make sure t
 
 [27] Redko I., Courty N., Flamary R., Tuia D. (2019). [Optimal Transport for Multi-source Domain Adaptation under Target Shift](http://proceedings.mlr.press/v89/redko19a.html), Proceedings of the Twenty-Second International Conference on Artificial Intelligence and Statistics (AISTATS) 22, 2019.
 
-[28] Caffarelli, L. A., McCann, R. J. (2020). [Free boundaries in optimal transport and Monge-Ampere obstacle problems](http://www.math.toronto.edu/~mccann/papers/annals2010.pdf), Annals of mathematics, 673-730.
+[28] Caffarelli, L. A., McCann, R. J. (2010). [Free boundaries in optimal transport and Monge-Ampere obstacle problems](http://www.math.toronto.edu/~mccann/papers/annals2010.pdf), Annals of mathematics, 673-730.
 
 [29] Chapel, L., Alaya, M., Gasso, G. (2019). [Partial Gromov-Wasserstein with Applications on Positive-Unlabeled Learning](https://arxiv.org/abs/2002.08276), arXiv preprint arXiv:2002.08276.
 

docs/source/readme.rst

@@ -434,7 +434,7 @@ Shift <http://proceedings.mlr.press/v89/redko19a.html>`__, Proceedings
 of the Twenty-Second International Conference on Artificial Intelligence
 and Statistics (AISTATS) 22, 2019.
 
-[28] Caffarelli, L. A., McCann, R. J. (2020). `Free boundaries in
+[28] Caffarelli, L. A., McCann, R. J. (2010). `Free boundaries in
 optimal transport and Monge-Ampere obstacle
 problems <http://www.math.toronto.edu/~mccann/papers/annals2010.pdf>`__,
 Annals of mathematics, 673-730.