diff --git a/postgres/get-row-count-for-most-recent-query.md b/postgres/get-row-count-for-most-recent-query.md
index 6f11000..49d60d4 100644
--- a/postgres/get-row-count-for-most-recent-query.md
+++ b/postgres/get-row-count-for-most-recent-query.md
@@ -61,3 +61,5 @@ Time: 2.804 ms
 > \echo :ROW_COUNT
 3
 ```
+
+[source](https://postgresql.verite.pro/blog/2024/05/13/advanced-psql-coproc.html)