diff --git a/fastapi_book_server/app/serializers/book.py b/fastapi_book_server/app/serializers/book.py
index ec90a7c..b466a9b 100644
--- a/fastapi_book_server/app/serializers/book.py
+++ b/fastapi_book_server/app/serializers/book.py
@@ -1,4 +1,5 @@
 from datetime import date
+from typing import Optional
 
 from pydantic import BaseModel
 
@@ -37,3 +38,4 @@ class BookDetail(RemoteBook):
     sequences: list[Sequence]
     genres: list[BookGenre]
     is_deleted: bool
+    pages: Optional[int]