diff --git a/README.md b/README.md
index 17e6923..8b98283 100644
--- a/README.md
+++ b/README.md
@@ -1279,6 +1279,11 @@ Promise.cooperative()
 
 #### `<promise-coop>.set(..)`
 
+```bnf
+<promise-coop>.set(<value>)
+    -> <promise-coop>
+```
+
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