diff --git a/notebooks/hotair-box.ipynb b/notebooks/hotair-box.ipynb
index be2d3cb..4b39f8e 100644
--- a/notebooks/hotair-box.ipynb
+++ b/notebooks/hotair-box.ipynb
@@ -23,12 +23,14 @@
    "source": [
     "## Hot air balloon - lift calculator\n",
     "### Box shape\n",
-    "[Source code](https://gitea.citizen4.eu/sp9unb/balloon-calc) "
+    "[Source code](https://gitea.citizen4.eu/sp9unb/balloon-calc) \n",
+    "\n",
+    "[Run in mybinder.org IDE](https://mybinder.org/v2/git/https%3A%2F%2Fgitea.citizen4.eu%2Fsp9unb%2Fballoon-calc/HEAD?labpath=work%2Fhotair-box.ipynb) "
    ]
   },
   {
    "cell_type": "code",
-   "execution_count": 86,
+   "execution_count": 1,
    "id": "6ea87a15-f571-4611-8487-5b7556e2ef45",
    "metadata": {
     "extensions": {
@@ -66,7 +68,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 87,
+   "execution_count": 2,
    "id": "d075a994-76bb-46f7-bdfb-cc6ef449dc43",
    "metadata": {
     "extensions": {
@@ -105,7 +107,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 3,
    "id": "2f3b63fd-d5ea-40b6-a2f9-b31c84cfef36",
    "metadata": {
     "extensions": {
@@ -123,7 +125,22 @@
      }
     }
    },
-   "outputs": [],
+   "outputs": [
+    {
+     "data": {
+      "application/vnd.jupyter.widget-view+json": {
+       "model_id": "68aa2b284295445fbd69f50a344827cc",
+       "version_major": 2,
+       "version_minor": 0
+      },
+      "text/plain": [
+       "interactive(children=(FloatSlider(value=2.0, description='Width [m]:', layout=Layout(width='500px'), max=5.0, …"
+      ]
+     },
+     "metadata": {},
+     "output_type": "display_data"
+    }
+   ],
    "source": [
     "def f(width,height,depth,airTemp,hotAirTemp,coatDens):\n",
     "    print(\"\\n\")\n",
@@ -194,6 +211,14 @@
     "    coatDens=widgets.FloatSlider(min=1, max=50, step=1.0, value=15.0, description='Coating density [g/m2]:',readout_format='.0f',layout=layout,style=style)                  \n",
     "                );\n"
    ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "f57a4d40-ce23-4f32-941a-e085689fa6cf",
+   "metadata": {},
+   "outputs": [],
+   "source": []
   }
  ],
  "metadata": {
diff --git a/notebooks/hotair-pyramid.ipynb b/notebooks/hotair-pyramid.ipynb
index 79e4636..9958344 100644
--- a/notebooks/hotair-pyramid.ipynb
+++ b/notebooks/hotair-pyramid.ipynb
@@ -23,12 +23,14 @@
    "source": [
     "## Hot air balloon - lift calculator\n",
     "### Inverted pyramid shape\n",
-    "[Source code](https://gitea.citizen4.eu/sp9unb/balloon-calc) "
+    "[Source code](https://gitea.citizen4.eu/sp9unb/balloon-calc) \n",
+    "\n",
+    "[Run in mybinder.org IDE](https://mybinder.org/v2/git/https%3A%2F%2Fgitea.citizen4.eu%2Fsp9unb%2Fballoon-calc/HEAD?labpath=work%2Fhotair-pyramid.ipynb) "
    ]
   },
   {
    "cell_type": "code",
-   "execution_count": 35,
+   "execution_count": 1,
    "id": "6ea87a15-f571-4611-8487-5b7556e2ef45",
    "metadata": {
     "extensions": {
@@ -69,7 +71,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 36,
+   "execution_count": 2,
    "id": "d075a994-76bb-46f7-bdfb-cc6ef449dc43",
    "metadata": {
     "extensions": {
@@ -108,7 +110,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 39,
+   "execution_count": 3,
    "id": "229c0a36-bf1f-4c07-884c-f3522d5eaae5",
    "metadata": {},
    "outputs": [],
@@ -138,7 +140,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 40,
+   "execution_count": 4,
    "id": "2f3b63fd-d5ea-40b6-a2f9-b31c84cfef36",
    "metadata": {
     "extensions": {
@@ -160,7 +162,7 @@
     {
      "data": {
       "application/vnd.jupyter.widget-view+json": {
-       "model_id": "60a4721d0e034caabff5f13695af2a7b",
+       "model_id": "bedefd6b566a49efbb902f1ee4ce51a0",
        "version_major": 2,
        "version_minor": 0
       },