diff --git a/doc/articles/custom-installers.md b/doc/articles/custom-installers.md
index 98a9a2212..5cf93a9e7 100644
--- a/doc/articles/custom-installers.md
+++ b/doc/articles/custom-installers.md
@@ -51,7 +51,7 @@ An example composer.json of such a template package would be:
 ## Creating an Installer
 
 A Custom Installer is defined as a class that implements the
-[`Composer\Installer\InstallerInterface`][3] and is usually distributed in a
+[`Composer\Installer\InstallerInterface`][4] and is usually distributed in a
 Composer Plugin.
 
 A basic Installer Plugin would thus compose of three files: