diff --git a/src/constitutive/hyperelastic_damage/buche_silberstein/py.rs b/src/constitutive/hyperelastic_damage/buche_silberstein/py.rs
index 8e4646ba..a4e80db8 100644
--- a/src/constitutive/hyperelastic_damage/buche_silberstein/py.rs
+++ b/src/constitutive/hyperelastic_damage/buche_silberstein/py.rs
@@ -107,11 +107,11 @@ impl BucheSilberstein
                 &self.element, &self.factor, &self.grid, &self.normalization, &self.method,
                 &self.nondimensional_critical_extension, &self.nondimensional_link_stiffness,
                 &self.number_of_links, &self.swelling_ratio,
-                &stretch, &maximum_previous_stretch
+                stretch, &maximum_previous_stretch
             )
         }).collect::<Vec<[f64; 2]>>();
         let results_1 = results.iter().map(|result| result[0]).collect();
         let results_2 = results.iter().map(|result| result[1]).collect();
         (PyArray::from_vec(py, results_1).to_dyn(), PyArray::from_vec(py, results_2).to_dyn())
     }
-}
\ No newline at end of file
+}