diff --git a/README.md b/README.md
index 5d3bd45..f16590a 100644
--- a/README.md
+++ b/README.md
@@ -94,7 +94,7 @@
 * [开源世界旅行手册](http://i.linuxtoy.org/docs/guide/index.html)
 * [鸟哥的Linux私房菜](http://linux.vbird.org/)
 * [The Linux Command Line](http://billie66.github.io/TLCL/index.html) (中英文版)
-* [Linux 设备驱动](http://oss.org.cn/kernel-book/ldd3/index.html) (第三版)
+* [Linux 设备驱动](http://oss.org.cn/kernel-book/ldd3/index.html) (第三版):worried:
 * [深入分析Linux内核源码](http://www.kerneltravel.net/kernel-book/%E6%B7%B1%E5%85%A5%E5%88%86%E6%9E%90Linux%E5%86%85%E6%A0%B8%E6%BA%90%E7%A0%81.html) :worried:
 * [UNIX TOOLBOX](http://cb.vu/unixtoolbox_zh_CN.xhtml)
 * [Docker中文指南](https://github.com/widuu/chinese_docker)