diff --git a/sources/README.md b/sources/README.md
index bf366c7..12157f5 100644
--- a/sources/README.md
+++ b/sources/README.md
@@ -7,3 +7,7 @@ The `patterns/` directory is **prescriptive** — it tells you what to do.
 
 Patterns that prove broadly applicable get promoted from here into `patterns/`.
 The rest stays as reference for understanding how mature projects solve specific problems.
+
+## Origin
+
+All patterns in this repo were extracted from the [Rust standard library](https://github.com/rust-lang/rust) (`library/` directory) at commit [`f53b654`](https://github.com/rust-lang/rust/tree/f53b654a8882fd5fc036c4ca7a4ff41ce32497a6) — 325,000 commits, 8,021 contributors.