diff --git a/mkdocs.yml b/mkdocs.yml
index b99cac2048727a02350746bdfc1a14f0e253b540..f6003e2bc1da69d05b0fdfc1f042efac9947876f 100644
--- a/mkdocs.yml
+++ b/mkdocs.yml
@@ -37,8 +37,8 @@ nav:
   - Solutions:
     - Einstein model: '1_einstein_model_solutions.md'
     - Debye model: '2_debye_model_solutions.md'
-    - Crystal structure: '9_crystal_structure_solutions.md'
-    - X-ray diffraction: '10_xray_solutions.md'
+    #- Crystal structure: '9_crystal_structure_solutions.md'
+    #- X-ray diffraction: '10_xray_solutions.md'
  
 
 theme: