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@@ -39,12 +39,12 @@ I. [Predecessors of Quantum Mechanics – Key Mathematicians and Their Contribut
    5. [Satyendra Nath Bose (1924)](#satyendra-nath-bose-1924)  
 
 II. [Early 20th Century – Foundations of Quantum Mechanics](#early-20th-century-foundations-of-quantum-mechanics)  
-   6. [Max Planck (1900)](#max-planck-1900)  
-   7. [Albert Einstein (1905)](#albert-einstein-1905)  
-   8. [Niels Bohr (1913)](#niels-bohr-1913)  
-   9. [Erwin Schrödinger (1926)](#erwin-schroedinger-1926)  
-   10. [Werner Heisenberg (1927)](#werner-heisenberg-1927)  
-   11. [Paul Dirac (1928)](#paul-dirac-1928)  
+    6. [Max Planck (1900)](#max-planck-1900)  
+    7. [Albert Einstein (1905)](#albert-einstein-1905)  
+    8. [Niels Bohr (1913)](#niels-bohr-1913)  
+    9. [Erwin Schrödinger (1926)](#erwin-schroedinger-1926)  
+    10. [Werner Heisenberg (1927)](#werner-heisenberg-1927)  
+    11. [Paul Dirac (1928)](#paul-dirac-1928)  
 
 III. [Mid-20th Century – Foundation for Quantum Information](#mid-20th-century-foundation-for-quantum-information)  
    12. [John von Neumann (1932)](#john-von-neumann-1932)