diff --git a/README.md b/README.md
index fbca07c..b99a4e6 100644
--- a/README.md
+++ b/README.md
@@ -14,7 +14,7 @@ Some of the fine books I have read
 
 ## b01-数学
 
-### 《程序员的数学》
+### [《程序员的数学》](a.md)
 
 ``` html
 【作者】：平冈和幸堀玄著