diff --git a/chapter2/helmholtz_code.ipynb b/chapter2/helmholtz_code.ipynb
index c33bcace..fd8ac14c 100644
--- a/chapter2/helmholtz_code.ipynb
+++ b/chapter2/helmholtz_code.ipynb
@@ -15,7 +15,7 @@
     "## Test problem\n",
     "As an example, we will model a plane wave propagating in a tube.\n",
     "While it is a basic test case, the code can be adapted to way more complex problems where velocity and impedance boundary conditions are needed.\n",
-    "We will apply a velocity boundary condition $v_n = 0.001$ to one end of the tube and an impedance $Z$ computed with the Delaney-Bazley model,\n",
+    "We will apply a velocity boundary condition $v_n = 0.001$ to one end of the tube (for the sake of simplicity, in this basic example, we are ignoring the point source, which can be applied with scifem) and an impedance $Z$ computed with the Delaney-Bazley model,\n",
     "supposing that a layer of thickness $d = 0.02$ and flow resistivity $\\sigma = 1e4$ is placed at the second end of the tube.\n",
     "The choice of such impedance (the one of a plane wave propagating in free field) will give, as a result, a solution with no reflections.\n",
     "\n",
diff --git a/chapter2/helmholtz_code.py b/chapter2/helmholtz_code.py
index 2eee4715..e4b93ed9 100644
--- a/chapter2/helmholtz_code.py
+++ b/chapter2/helmholtz_code.py
@@ -24,7 +24,7 @@
 # ## Test problem
 # As an example, we will model a plane wave propagating in a tube.
 # While it is a basic test case, the code can be adapted to way more complex problems where velocity and impedance boundary conditions are needed.
-# We will apply a velocity boundary condition $v_n = 0.001$ to one end of the tube and an impedance $Z$ computed with the Delaney-Bazley model,
+# We will apply a velocity boundary condition $v_n = 0.001$ to one end of the tube (for the sake of simplicity, in this basic example, we are ignoring the point source, which can be applied with scifem) and an impedance $Z$ computed with the Delaney-Bazley model,
 # supposing that a layer of thickness $d = 0.02$ and flow resistivity $\sigma = 1e4$ is placed at the second end of the tube.
 # The choice of such impedance (the one of a plane wave propagating in free field) will give, as a result, a solution with no reflections.
 #