diff --git a/source/part-1-workspace/maintainable-applications/_index.adoc b/source/part-1-workspace/maintainable-applications/_index.adoc
index cb98325..241a6dd 100644
--- a/source/part-1-workspace/maintainable-applications/_index.adoc
+++ b/source/part-1-workspace/maintainable-applications/_index.adoc
@@ -22,5 +22,7 @@ include::solid.adoc[]
 [quote]
 ----
 Tests are part of the system.
--- Robert C. Martin, Clean Architecture, page 250, Chapitre 28 - The Boundaries
+You can think of tests as the outermost circle in the architecture. 
+Nothing within in the system depends on the tests, and the tests always depend inward on the components of the system ».
+-- Robert C. Martin, Clean Architecture, page 203, Inner circle are policies, page 250, Chapitre 28 - The Boundaries
 ----
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