Update citation to VTR9

Updated the link and citation to VTR9

Author: vaughnbetz

_pages/download.md

@@ -29,14 +29,20 @@ permalink: /download/
 
 How to Cite
 ===========
-The following [paper](http://www.eecg.utoronto.ca/~kmurray/vtr/vtr8_trets.pdf) may be used as a general citation for VTR (bibtex format):
+The following [paper](https://dl.acm.org/doi/10.1145/3734798) may be used as a general citation for VTR (bibtex format):
 
-    @article{vtr8,
-      title={VTR 8: High Performance CAD and Customizable FPGA Architecture Modelling},
-      author={Murray, Kevin E. and Petelin, Oleg and Zhong, Sheng and Wang, Jai Min and ElDafrawy, Mohamed and Legault, Jean-Philippe and Sha, Eugene and Graham, Aaron G. and Wu, Jean and Walker, Matthew J. P. and Zeng, Hanqing and Patros, Panagiotis and Luu, Jason and Kent, Kenneth B. and Betz, Vaughn},
-      journal={ACM Trans. Reconfigurable Technol. Syst.},
-      year={2020}
-    }
+@article{vtr9,
+author = {Elgammal, Mohamed A. and Mohaghegh, Amin and Shahrouz, Soheil Gholami and Mahmoudi, Fatemehsadat and Ko\c{s}ar, Fahrican and Talaei, Kimia and Fife, Joshua and Khadivi, Daniel and Murray, Kevin and Boutros, Andrew and Kent, Kenneth B. and Goeders, Jeff and Betz, Vaughn},
+title = {VTR 9: Open-Source CAD for Fabric and Beyond FPGA Architecture Exploration},
+year = {2025},
+publisher = {Association for Computing Machinery},
+address = {New York, NY, USA},
+issn = {1936-7406},
+url = {https://doi.org/10.1145/3734798},
+doi = {10.1145/3734798},
+journal = {ACM Trans. Reconfigurable Technol. Syst.},
+month = May
+}
 
 License
 =======