diff --git a/src/exercises/day-1/book-library.md b/src/exercises/day-1/book-library.md
index 6678ff5c..34f9b0b1 100644
--- a/src/exercises/day-1/book-library.md
+++ b/src/exercises/day-1/book-library.md
@@ -40,3 +40,9 @@ Use this to create a library application. Copy the code below to
 
 {{#include book-library.rs:main}}
 ```
+
+<details>
+    
+[Solution](solutions-afternoon.md#designing-a-library)
+
+</details>