diff --git a/Examples/BatteryStateful_CustomLifeModel.ipynb b/Examples/BatteryStateful_CustomLifeModel.ipynb
index 507c89b..dcbaf30 100644
--- a/Examples/BatteryStateful_CustomLifeModel.ipynb
+++ b/Examples/BatteryStateful_CustomLifeModel.ipynb
@@ -36,6 +36,11 @@
     "\n",
     "\n",
     "class LifeModel:\n",
+    "    \"\"\"\n",
+    "    Reference for NMC/Graphite and LMO/LTO life models:\n",
+    "    Guittet, D. Levelized cost of charging of extreme fast charging with stationary LMO/LTO batteries. Journal of Energy Storage. 2024. \n",
+    "    https://www.sciencedirect.com/science/article/pii/S2352152X2400152X\n",
+    "    \"\"\"\n",
     "    def __init__(self, size_kwh, pVars=[], pVals=[]) -> None:\n",
     "        self.size_kwh = size_kwh\n",
     "        self.p = {k: v for k, v in zip(pVars, pVals)}\n",