diff --git a/app.js b/app.js
index 69366c9..2c21880 100644
--- a/app.js
+++ b/app.js
@@ -48,6 +48,8 @@ function deleteBook(bookId) {
 
     let rowElement = document.getElementById("bookRow"+bookId);
     bookTable.removeChild(rowElement);
+
+    delete books[bookId];
 }
 
 function editBook(bookId) {