diff --git a/_docs/06-wrap-up.md b/_docs/06-wrap-up.md
index d23bd7a..9d8853b 100644
--- a/_docs/06-wrap-up.md
+++ b/_docs/06-wrap-up.md
@@ -67,6 +67,8 @@ Open {% include open-grafana.html %} to explore dashboards, traces, and logs.
 
 ## References
 
+> **About these books.** These are books we recommend, not books we wrote. We cite them as pointers into the originals; we do not copy from them, and this material is not a substitute for reading them. If a title is useful to you, please go read it in full.
+
 ### Books
 
 - Vlad Khononov -- *Learning Domain-Driven Design* (O'Reilly, 2021)
diff --git a/_docs/addendum-b-advanced-patterns.md b/_docs/addendum-b-advanced-patterns.md
index 7253b27..377bff8 100644
--- a/_docs/addendum-b-advanced-patterns.md
+++ b/_docs/addendum-b-advanced-patterns.md
@@ -396,6 +396,8 @@ A practical framework for reducing observability costs without losing debugging
 
 ## 7. Further Reading
 
+> **About these books.** These are books we recommend, not books we wrote. We cite them as pointers into the originals; we do not copy from them, and this material is not a substitute for reading them. If a title is useful to you, please go read it in full.
+
 ### Books referenced in this addendum
 
 - Alessandro Colla -- *Domain-Driven Refactoring* (Independently published, 2024). Saga compensation patterns, choreography vs orchestration, and practical refactoring techniques.