added missing link

Author: simongravelle

docs/sphinx/source/tutorial3/tutorial.rst

@@ -90,9 +90,13 @@ distances, etc).  Thus add to **water.lmp** the line:
     maps are used for the bond types, angle types, and dihedral types.
 
 Let us create water molecules.  To do so, let us import a molecule template called
-**water.mol** and then randomly create 700 molecules.  Add the following
+|water_mol_tutorial3| and then randomly create 700 molecules.  Add the following
 lines into **water.lmp**:
 
+.. |water_mol_tutorial3| raw:: html
+
+    <a href="https://raw.githubusercontent.com/lammpstutorials/lammpstutorials-inputs/refs/heads/main/tutorial3/water.mol" target="_blank">water.mol</a>
+
 .. code-block:: lammps
 
     molecule h2omol water.mol