diff --git a/Readings.md b/Readings.md
index 461024ef..5ccbd978 100644
--- a/Readings.md
+++ b/Readings.md
@@ -29,4 +29,10 @@ Limits of recusrion schemes? Maybe a hylo can help to implement the list filter?
## Cheat Sheet
+### Recursion schemes
+
+
+### Algebras
+
+
diff --git a/images/algebras.svg b/images/algebras.svg
new file mode 100644
index 00000000..205cadb6
--- /dev/null
+++ b/images/algebras.svg
@@ -0,0 +1,4858 @@
+
+