diff --git a/docs/lambda-k-pi/index.md b/docs/lambda-k-pi/index.md
index 78a8251..9511398 100644
--- a/docs/lambda-k-pi/index.md
+++ b/docs/lambda-k-pi/index.md
@@ -3,4 +3,5 @@
 ```{toctree}
 ampform
 ampform-dpd
+manual-dpd
 ```
diff --git a/docs/lambda-k-pi/manual-dpd.ipynb b/docs/lambda-k-pi/manual-dpd.ipynb
new file mode 100644
index 0000000..cec10be
--- /dev/null
+++ b/docs/lambda-k-pi/manual-dpd.ipynb
@@ -0,0 +1,72 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Manually modelling helicity amplitudes"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "The goal in this notebook is to formulate helicity amplitude model manually and reproduce the result in [Amplitude model with `ampform-dpd` notebook](ampform-dpd.ipynb)."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "jupyter": {
+     "source_hidden": true
+    },
+    "tags": [
+     "hide-cell"
+    ]
+   },
+   "outputs": [],
+   "source": [
+    "from __future__ import annotations\n",
+    "\n",
+    "import logging\n",
+    "import os\n",
+    "import warnings\n",
+    "\n",
+    "STATIC_PAGE = \"EXECUTE_NB\" in os.environ\n",
+    "\n",
+    "os.environ[\"TF_CPP_MIN_LOG_LEVEL\"] = \"3\"\n",
+    "logging.disable(logging.WARNING)\n",
+    "warnings.filterwarnings(\"ignore\")"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Model implementation"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3 (ipykernel)",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.12.5"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 4
+}