Merge pull request #107 from coq/mattam82-patch-1

Update 9.0.md

Author: tabareau

data/releases/9.0.md

@@ -22,15 +22,14 @@ highlights: |
 
 ## Changes 
 
-See the full [changelog](https://rocq-prover.org/doc/V9.0/refman/changes.html#changes-in-9-0-0) in the reference manual.
+See the full [changelog](https://rocq-prover.org/doc/V9.0.0/refman/changes.html#changes-in-9-0-0) in the reference manual.
 
 ## Installation Instructions
 
 The base proof assistant can be installed as an opam switch with the following commands:
 ```bash
 opam update
 opam switch create 4.14.1
-opam repo add coq-core-dev https://coq.inria.fr/opam/core-dev
 opam install rocq-prover.9.0.0
 ```
 
@@ -40,11 +39,11 @@ Source Distribution
 -------------------
 
 - [Source
-  tarball](https://github.com/coq/coq/archive/refs/tags/V9.0.tar.gz)
+  tarball](https://github.com/coq/coq/releases/download/V9.0.0/rocq-9.0.0.tar.gz)
   (`.tar.gz`) for compilation under Unix (including Linux and macOS X)
   and Microsoft Windows (including Cygwin).
 - Also available in
-  [`.zip`](https://github.com/coq/coq/archive/refs/tags/V9.0.zip)
+  [`.zip`](https://github.com/coq/coq/releases/download/V9.0.0/rocq-9.0.0.zip)
   format.
 - [Opam](https://opam.ocaml.org/) is a source-based distribution of
   OCaml, Rocq and many companion libraries and tools. Compilation and