diff --git a/docs/src/images/plot_67.svg b/docs/src/images/plot_67.svg
new file mode 100644
index 0000000..8209e9d
--- /dev/null
+++ b/docs/src/images/plot_67.svg
@@ -0,0 +1,5 @@
+<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" width="173.205081" height="150" viewBox="0 0 173.205081 150">
+<path fill-rule="nonzero" fill="rgb(22%, 59.6%, 14.9%)" fill-opacity="1" d="M 86.601562 0 L 127.738281 71.25 L 86.601562 95 L 45.464844 71.25 L 86.601562 0 "></path>
+<path fill-rule="nonzero" fill="rgb(58.4%, 34.5%, 69.8%)" fill-opacity="1" d="M 173.207031 150 L 90.933594 150 L 90.933594 102.5 L 132.070312 78.75 L 173.207031 150 "></path>
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+</svg>
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