diff --git a/modules/seq/alg/doc/seqalg.rst b/modules/seq/alg/doc/seqalg.rst
index d3c2b51d2c173e86df67f1ba9fc608ec94ac9984..caa671577b193a6360cb05ed24a4860309431905 100644
--- a/modules/seq/alg/doc/seqalg.rst
+++ b/modules/seq/alg/doc/seqalg.rst
@@ -256,7 +256,7 @@ Algorithms for Alignments
   :rtype: float
 
 
-.. _substitution-weight-matrices
+.. _substitution-weight-matrices:
 
 Substitution Weight Matrices and BLOSUM Matrices
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