diff --git a/book/assets/drawio/ops-signed-message.drawio b/book/assets/drawio/ops-signed-message.drawio
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diff --git a/book/assets/drawio/ops-signed-message.svg b/book/assets/drawio/ops-signed-message.svg
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\ No newline at end of file
diff --git a/book/source/signing_data.md b/book/source/signing_data.md
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--- a/book/source/signing_data.md
+++ b/book/source/signing_data.md
@@ -74,6 +74,13 @@ A {term}`one-pass signed` {term}`OpenPGP message` consi
3. **{term}`Data signature packets`**: These contain the {term}`cryptographic signature` corresponding to the original data.
+```{figure} plain_svg/ops-signed-message.svg
+:name: fig-ops-signed-message
+:alt: Depicts the structure of a one-pass-signed message.
+
+The structure of a one-pass signed message.
+```
+
```{note}
Despite its name, a {term}`one-pass signature packet` is not a type of {term}`signature packet`.