Update draft-ietf-lamps-pq-composite-sigs.md

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draft-ietf-lamps-pq-composite-sigs.md

@@ -662,6 +662,14 @@ Note that in step 4 above, the function fails early if the first component fails
 ## SerializeKey and DeserializeKey
 
 The serialization routine for keys simply concatenates the fixed-length public or private keys of the component signatures, as defined below:
+~~~
+Composite-ML-DSA.SerializeKey(key) -> bytes
+
+~~~
+{: #alg-composite-serialize title="Composite SerializeKey(pk)"}
+
+Deserialization reverses this process, raising an error in the event that the input is malformed.
+
 
 # Composite Key Structures {#sec-composite-structs}