diff --git a/doc/src/pair_coul.rst b/doc/src/pair_coul.rst
index dce5c96518..b98de91fd0 100644
--- a/doc/src/pair_coul.rst
+++ b/doc/src/pair_coul.rst
@@ -471,7 +471,7 @@ Phys, 110, 8254 (1999).
 .. _Plummer1:
 
 **(Plummer)** G. Plummer, J. P. Tavenner, M. I. Mendelev, Z. Wu, J. W. Lawson,
-J Chemical Physics, 162, 054709 (2025)
+J Chemical Physics, 162, 054709 (2025).
 
 .. _Jorgensen3: