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diff --git a/index.ipynb b/index.ipynb
index af1b5a094758196b0eeeb43c71ca7a757373ffb4..c5dac8c31ae2dd74c2abb45d2e11b9f187d8b518 100644
--- a/index.ipynb
+++ b/index.ipynb
@@ -133,8 +133,13 @@
     "\n",
     " - 1.1 A roadmap through the BMCS landscape\n",
     " - 1.2 Introduction to Jupyter Web Apps and notebooks (mathematics and mechanics support)\n",
-    " - 1.3 [Example Elastic mixture rule](bmcs_course/1_1_elastic_stiffness_of_the_composite.ipynb)\n",
-    " \n",
+    " - 1.3 [Example Elastic mixture rule](bmcs_course/1_1_elastic_stiffness_of_the_composite.ipynb)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
     "## Tour 2\n",
     "\n",
     "### Material and cross-section\n",
@@ -147,31 +152,56 @@
     "### Cross section and structure \n",
     "\n",
     "- 2.6 [Anchorage]\n",
-    "- 2.7 [Multiple cracking]\n",
-    "\n",
+    "- 2.7 [Multiple cracking]"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
     "## Tour 3\n",
     "- 3.1 [Pull-out with softening and hardening](bmcs_course/3_1_PO_LF_LM_EL_FE_CB.ipynb) \n",
     "- 3.2 [EXTRA - Newton iterative scheme](extras/newton_method.ipynb)\n",
-    "- 3.2 [EXTRA - Nonlinear finite-element solver for 1d pullout](extras/pullout1d.ipynb)\n",
-    "\n",
+    "- 3.2 [EXTRA - Nonlinear finite-element solver for 1d pullout](extras/pullout1d.ipynb)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
     "## Tour 4\n",
     "\n",
     "- 4.1 [Unloading with multi-linear bond-slip law](bmcs_course/4_1_PO_multilinear_unloading.ipynb)\n",
     "- 4.2 [Basic concept of plasticity, ideal and isotropic hardening](bmcs_course/4_2_BS_EP_SH_I_A.ipynb) \n",
     "- 4.3 [Basic concept of plasticity, kinematic hardening](bmcs_course/4_3_BS_EP_SH_IK_A.ipynb)\n",
-    "- 4.4 [EXTRA - Generalization of the algorithm using vectors](bmcs_course/4_4_BS_EP_SH_IK_N.ipynb) \n",
-    "\n",
+    "- 4.4 [EXTRA - Generalization of the algorithm using vectors](bmcs_course/4_4_BS_EP_SH_IK_N.ipynb) "
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
     "## Tour 5\n",
     "- 5.1 [Damage initiation, damage evolution, 2D bond behavior](bmcs_course/5_1_Introspect_Damage_Evolution_Damage_initiation.ipynb)\n",
-    "- 5.2 [Pull out simulation using damage model](bmcs_course/5_2_PO_DM_FRP_N.ipynb)\n",
-    "\n",
+    "- 5.2 [Pull out simulation using damage model](bmcs_course/5_2_PO_DM_FRP_N.ipynb)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
     "## Tour 6\n",
     "\n",
-    "- 6.1 Crack propagation\n",
-    "\n",
+    "- 6.1 Crack propagation"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
     "## Tour 7\n",
     "\n",
-    "- 7.1 Beam bending \n"
+    "- 7.1 Beam bending "
    ]
   }
  ],