Merge pull request #242 from sophie-h/sophie-h/fix-book-link

Fix book link

Author: GuillaumeGomez

index.md

@@ -37,7 +37,7 @@ The following table contains the most popular crates of **gtk-rs**. More informa
 
 Julian Hofer is writing a book titled [GUI development with Rust and GTK 4][book]. We recommend both new and experienced **gtk-rs** users to have a look at it. While this book is targeted at people who want to develop GTK 4 applications, it also covers more general aspects of the GNOME stack such as **GObject Concepts**, **The Main Event Loop** and **GSettings**.
 
-[book]: /gtk4-rs/stable/book
+[book]: /gtk4-rs/stable/latest/book
 
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