diff --git a/doc/manual/packages/s3-substituter.xml b/doc/manual/packages/s3-substituter.xml
index e7589ffdb..1722090ef 100644
--- a/doc/manual/packages/s3-substituter.xml
+++ b/doc/manual/packages/s3-substituter.xml
@@ -113,7 +113,7 @@ the S3 URL:
exactly s3://example-nix-cache.
Nix will use the default
+ xlink:href="https://docs.aws.amazon.com/sdk-for-cpp/v1/developer-guide/credentials.html">default
credential provider chain for authenticating requests to
Amazon S3.
@@ -138,7 +138,7 @@ the S3 URL:
be s3://example-nix-cache.
Nix will use the default
+ xlink:href="https://docs.aws.amazon.com/sdk-for-cpp/v1/developer-guide/credentials.html">default
credential provider chain for authenticating requests to
Amazon S3.