diff --git a/12_c_plus_plus_and_python/Makefile b/12_c_plus_plus_and_python/Makefile
index 1aaf41e..48b0be4 100755
--- a/12_c_plus_plus_and_python/Makefile
+++ b/12_c_plus_plus_and_python/Makefile
@@ -1,4 +1,4 @@
-all: lectures_00_intro_compilation practical_day_1 
+all: practical
 
 lectures_dir = lectures
 practicals_dir = practicals
@@ -17,7 +17,7 @@ lectures%:${lectures_dir}/lectures%.md
 project%:${projects_dir}/project%.md
 	pandoc  -f markdown$(extensions) $(pdf_template) $^ -o ${publish_dir}/$@.pdf
 
-practical%:${practicals_dir}/practical%.md
+practical:${practicals_dir}/practical.md
 	pandoc  -f markdown$(extensions) $(pdf_template) $^ -o ${publish_dir}/$@.pdf
 
 clean:
diff --git a/12_c_plus_plus_and_python/practicals/practical.md b/12_c_plus_plus_and_python/practicals/practical.md
index 04ae70b..2d5cf7b 100755
--- a/12_c_plus_plus_and_python/practicals/practical.md
+++ b/12_c_plus_plus_and_python/practicals/practical.md
@@ -15,9 +15,9 @@ link-citations: true
 
 This practical uses a model of cell diffusion and excluded volume interaction. It is not
 required that you understand the details of the model, as it is implemented for you in
-the file `excluded_volume_diffusion.py`. The purpose of this practical is to profile and
-increase the efficiency of the model using numpy vectorisation and C++. The details of
-the model are provided below.
+the python module contain in the `cell_model` directory. The purpose of this practical
+is to profile and increase the efficiency of the model using numpy vectorisation and
+C++. The details of the model are provided below.
 
 The model consists of a set of $N$ cells in a periodic unit square domain. Let
 $\bfX_i(t)$ denote the position of the $i$th particle in $\Omega \subset \mathbb R^2$.
diff --git a/12_c_plus_plus_and_python/publish/.gitignore b/12_c_plus_plus_and_python/publish/.gitignore
new file mode 100644
index 0000000..e69de29
diff --git a/12_c_plus_plus_and_python/publish/cell_model b/12_c_plus_plus_and_python/publish/cell_model
new file mode 120000
index 0000000..b5f520b
--- /dev/null
+++ b/12_c_plus_plus_and_python/publish/cell_model
@@ -0,0 +1 @@
+practicals/cell_model
\ No newline at end of file