diff --git a/glossary.md b/glossary.md
index 6cf8a46c5c1cb..9022cbea332aa 100644
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@@ -172,4 +172,4 @@ Top SQL helps locate SQL queries that contribute to a high load of a TiDB or TiK
 
 ### TSO
 
-Because TiKV is a distributed storage system, it requires a global timing service, Timestamp Oracle (TSO), to assign a monotonically increasing timestamp. In TiKV, such a feature is provided by PD, and in Google [Spanner](http://static.googleusercontent.com/media/research.google.com/en//archive/spanner-osdi2012.pdf), this feature is provided by multiple atomic clocks and GPS.
+Because TiKV is a distributed storage system, it requires a global timing service, Timestamp Oracle (TSO), to assign a monotonically increasing timestamp. In TiKV, such a feature is provided by PD, and in Google [Spanner](http://static.googleusercontent.com/media/research.google.com/en//archive/spanner-osdi2012.pdf), this feature is provided by multiple atomic clocks and GPS. For details, see [TSO](/tso.md).