Update README.md

Author: Mirko-Nava

README.md

@@ -24,13 +24,13 @@ The preprint PDF of the article is available at the following link [arXiv:1809.0
 
 ### Bibtex
 
-```properties  
+```properties
 @article{nava2019learning, 
 author={M. Nava and J. Guzzi and R. O. Chavez-Garcia and L. Gambardella and A. Giusti}, 
 journal={IEEE Robotics and Automation Letters}, 
 title={Learning Long-Range Perception Using Self-Supervision from Short-Range Sensors and Odometry}, 
 year={2019},
-keywords={Range Sensing;Computer Vision for Other Robotic Applications;Deep Learning in Robotics and Automation}, 
+keywords={Range Sensing,Computer Vision for Other Robotic Applications,Deep Learning in Robotics and Automation}, 
 doi={10.1109/LRA.2019.2894849}, 
 ISSN={2377-3766},
 }