diff --git a/README.md b/README.md
index 206fff2..66d76f7 100644
--- a/README.md
+++ b/README.md
@@ -8,5 +8,11 @@ To add a cover just drop the file in the `covers` folder.
 Convention for the filename is:
 
 ```
-title-of-the-book_author-name
+number_title-of-the-book_author-name
+```
+
+ex.
+
+```
+02_Shaping-Things_Bruce-Sterling.png
 ```
diff --git a/covers/The-Interfact_Gabriel-Yoran.png b/covers/01_The-Interfact_Gabriel-Yoran.png
similarity index 100%
rename from covers/The-Interfact_Gabriel-Yoran.png
rename to covers/01_The-Interfact_Gabriel-Yoran.png
diff --git a/covers/Shaping-Things_Bruce-Sterling.png b/covers/02_Shaping-Things_Bruce-Sterling.png
similarity index 100%
rename from covers/Shaping-Things_Bruce-Sterling.png
rename to covers/02_Shaping-Things_Bruce-Sterling.png
diff --git a/covers/03_Literate-Programming_Donald-Knuth.png b/covers/03_Literate-Programming_Donald-Knuth.png
new file mode 100644
index 0000000..9071855
Binary files /dev/null and b/covers/03_Literate-Programming_Donald-Knuth.png differ