README.md: add link to blog announcement
Change-Id: Ibeddd40f2a11bfb4ec60f917341513349e788f56
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/222697
Reviewed-by: Damien Neil <dneil@google.com>
diff --git a/README.md b/README.md
index b0a4117..103f522 100644
--- a/README.md
+++ b/README.md
@@ -173,8 +173,9 @@
## Historical legacy
-This project is the second major revision (released in 2020) of the Go protocol
-buffer API implemented by the
+This project is the second major revision
+([released in 2020](https://blog.golang.org/a-new-go-api-for-protocol-buffers))
+of the Go protocol buffer API implemented by the
[`google.golang.org/protobuf`](https://pkg.go.dev/mod/google.golang.org/protobuf)
module. The first major version
([released publicly in 2010](https://blog.golang.org/third-party-libraries-goprotobuf-and))
