diff --git a/Cargo.toml b/Cargo.toml
index 920b11c..eb3a7d7 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -24,4 +24,10 @@ members = ["unindent"]
 
 [package.metadata.docs.rs]
 targets = ["x86_64-unknown-linux-gnu"]
-rustdoc-args = ["--generate-link-to-definition"]
+rustdoc-args = [
+    "--generate-link-to-definition",
+    "--extern-html-root-url=core=https://doc.rust-lang.org",
+    "--extern-html-root-url=alloc=https://doc.rust-lang.org",
+    "--extern-html-root-url=std=https://doc.rust-lang.org",
+    "--extern-html-root-url=proc_macro=https://doc.rust-lang.org",
+]
diff --git a/unindent/Cargo.toml b/unindent/Cargo.toml
index d7410a0..bab50fb 100644
--- a/unindent/Cargo.toml
+++ b/unindent/Cargo.toml
@@ -12,4 +12,9 @@ repository = "https://github.com/dtolnay/indoc"
 
 [package.metadata.docs.rs]
 targets = ["x86_64-unknown-linux-gnu"]
-rustdoc-args = ["--generate-link-to-definition"]
+rustdoc-args = [
+    "--generate-link-to-definition",
+    "--extern-html-root-url=core=https://doc.rust-lang.org",
+    "--extern-html-root-url=alloc=https://doc.rust-lang.org",
+    "--extern-html-root-url=std=https://doc.rust-lang.org",
+]