diff --git a/Document/content/4.0_Domain_Specific_Testing.md b/Document/content/4.0_Domain_Specific_Testing.md
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--- a/Document/content/4.0_Domain_Specific_Testing.md
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-## Chapter 4: Domain-Specific Testing
+# Chapter 4: Domain-Specific Testing
 
 The AI Testing Guide framework is structured around four core layers of a typical AI Architecture:
 - Application Layer