Add references to the main VTR papers in the documentation.

Author: MohamedElgammal

doc/src/zreferences.rst

@@ -1,5 +1,18 @@
 Publications & References
 =========================
 
+How to cite
+-----------
+`M. A. Elgammal`, `A. Mohaghegh`, `S. G. Shahrouz`, `F. Mahmoudi`, `F. Kosar`, `K. Talaei`, `J. Fife`, `D. Khadivi`, `K. Murray`, `A. Boutros`, `K. B. Kent`, `J. Geoders`, and `V. Betz`, "VTR 9: Open-Source CAD for Fabric and Beyond FPGA Architecture Exploration," *ACM TRETS*, 2025.
+
+Previous Publications
+---------------------
+* `K. E. Murray`, `O. Petelin`, `S. Zhong`, `J. M. Wang`, `M. ElDafrawy`, `J.-P. Legault`, `E. Sha`, `A. G. Graham`, `J. Wu`, `M. J. P. Walker`, `H. Zeng`, `P. Patros`, `J. Luu`, `K. B. Kent` and `V. Betz`, "VTR 8: High Performance CAD and Customizable FPGA Architecture Modelling", *ACM TRETS*, 2020.
+
+* `J. LUU`, `J. Geoders`, `M. Wainberg`, `A. Somerville`, `T. Yu`, `K. Nasartschuk`, `M. Nasr`, `S. Wang`, `T. L`, `N. Ahmed`, `K. B. Kent`, `J. Anderson`, `J. Rose`, `V. Betz`, "VTR 7.0: Next Generation Architecture and CAD System for FPGAs", *ACM TRETS*, 2014.
+
+References
+----------
+
 .. bibliography:: z_references.bib
     :all: