diff --git a/examples/01_basic_example.ipynb b/examples/01_basic_example.ipynb
index e1041cf0..703e13b5 100644
--- a/examples/01_basic_example.ipynb
+++ b/examples/01_basic_example.ipynb
@@ -58,7 +58,7 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "From this we can construct `Obs`, which are the basic object of `pyerrors`. For each sample we give to the obs, we also have to specify an ensemble/replica name. In this example we assume that both datasets originate from the same gauge field ensemble labeled 'ensemble1'."
+    "From this we can construct `Obs`, which are the basic object of `pyerrors`. For each sample we give to the obs, we also have to specify an ensemble/replica name. In this example we assume that both datasets originate from the same gauge field ensemble labeled 'ensemble1'. **For correct error propagation it is crucial that observations from the same Monte Carlo chain are initialized with the same name.**"
    ]
   },
   {