diff --git a/notes b/notes
index af8befd..c6857be 100644
--- a/notes
+++ b/notes
@@ -209,4 +209,9 @@ references are immutable by default
 
 there can be one or multiple r/o references or only one mutable reference at a time
 
+https://doc.rust-lang.org/book/ch04-03-slices.html
+slices
+
+reference to a contiguous sequence of elements
+