Update README.md

Update reference

Author: Schmluk

README.md

@@ -25,12 +25,12 @@ An online volumetric mapping-based approach for real-time detection of diverse d
 # Paper
 If you find this package useful for your research, please consider citing our paper:
 
-* Lukas Schmid, Olov Andersson, Aurelio Sulser, Patrick Pfreundschuh, and Roland Siegwart. "**Dynablox: Real-time Detection of Diverse Dynamic Objects in Complex Environments**" in *ArXiv Preprint*, 2023. \[ [ArXiv](https://arxiv.org/abs/2304.10049) | [Video](https://www.youtube.com/watch?v=NA13fRWlqRQ) \]
+* Lukas Schmid, Olov Andersson, Aurelio Sulser, Patrick Pfreundschuh, and Roland Siegwart. "**Dynablox: Real-time Detection of Diverse Dynamic Objects in Complex Environments**" in *IEEE Robotics and Automation Letters (RA-L)*, 2023. \[ [ArXiv](https://arxiv.org/abs/2304.10049) | [Video](https://www.youtube.com/watch?v=NA13fRWlqRQ) \]
   ```bibtex
   @inproceedings{schmid2023dynablox,
     title={Dynablox: Real-time Detection of Diverse Dynamic Objects in Complex Environments},
     author={Schmid, Lukas, and Andersson, Olov, and Sulser, Aurelio, and Pfreundschuh, Patrick, and Siegwart, Roland},
-    booktitle={ArXiv Preprint 2304.10049},
+    booktitle={IEEE Robotics and Automation Letters},
     year={2023},
     volume={},
     number={},