diff --git a/cours/source/img/flowchart.drawio b/cours/source/img/flowchart.drawio
new file mode 100644
index 0000000..57e4a7d
--- /dev/null
+++ b/cours/source/img/flowchart.drawio
@@ -0,0 +1 @@
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diff --git a/cours/source/img/variables-references-and-values.drawio b/cours/source/img/variables-references-and-values.drawio
new file mode 100644
index 0000000..7fcd138
--- /dev/null
+++ b/cours/source/img/variables-references-and-values.drawio
@@ -0,0 +1 @@
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