diff --git a/.gitmodules b/.gitmodules
index 55dae027fe240ac941f09671c0ddc521eb9ad035..c614602cb8eb8d00a69da64953de2b1b93d583b7 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -1,3 +1,3 @@
 [submodule "book"]
 	path = book
-	url = https://github.com/PaddlePaddle/book.git
\ No newline at end of file
+	url = https://github.com/PaddlePaddle/book.git