diff --git a/flowcharts/sources.txt b/flowcharts/sources.txt
new file mode 100644
index 0000000..eda606e
--- /dev/null
+++ b/flowcharts/sources.txt
@@ -0,0 +1,2 @@
+https://xkcd.com/518/
+https://en.wikipedia.org/wiki/Flowchart