diff --git a/pages/common/tsort.md b/pages/common/tsort.md
index a8fafc6eda..6c99863621 100644
--- a/pages/common/tsort.md
+++ b/pages/common/tsort.md
@@ -2,6 +2,7 @@
 
 > Perform a topological sort.
 > A common use is to show the dependency order of nodes in a directed acyclic graph.
+> More information: <https://www.gnu.org/software/coreutils/manual/html_node/tsort-invocation.html>.
 
 - Perform a topological sort consistent with a partial sort per line of input separated by blanks: