Update README.md

Added line for paper citation.

README.md

@@ -17,7 +17,7 @@ the MaD TwinNet](http://arg.cs.tut.fi/demo/mad-twinnet).
 The paper of the MaD TwinNet is presented at the 
 [IEEE World Congress on Computational Intelligence (WCCI)/International
 Joint Conference on Neural Networks, 2018](http://www.ecomp.poli.br/~wcci2018/) and can be found
-online at [the corresponding arXiv entry](https://arxiv.org/abs/1802.00300).
+online at [the corresponding arXiv entry](https://arxiv.org/abs/1802.00300). If you find MaD TwinNet useful, please consider citing our paper. 
 
 If you need some help on using MaD TwinNet, please read the following
 instructions. 
@@ -230,4 +230,4 @@ agreement no [642685 MacSeNet](http://www.macsenet.eu/#0) (yes, in the video, is
 - The authors would like to thank [P. Magron](http://www.cs.tut.fi/~magron/index.html) 
 and 
 [G. Naithani](https://tutcris.tut.fi/portal/en/persons/gaurav-naithani(93c5b9b8-53ec-4651-8b06-c8f764a3703e).html) (TUT, Finland) for their 
-valuable comments and feedback during the writing process.
+valuable comments and feedback during the writing process.