diff --git a/zh-hans/lesson-13.md b/zh-hans/lesson-13.md
index 7fe48898..62201ec1 100644
--- a/zh-hans/lesson-13.md
+++ b/zh-hans/lesson-13.md
@@ -40,7 +40,7 @@ LaTeX 允许我们以可控的方式分割源文件。有两个重要的命令
 ```latex
 % !TEX program=lualatex
 
-\documentclass{ctexart}
+\documentclass{ctexbook}
 \usepackage{biblatex}
 \addbibresource{biblatex-examples.bib}