diff --git a/include/multigrid_pclomp/multigrid_ndt_omp_impl.hpp b/include/multigrid_pclomp/multigrid_ndt_omp_impl.hpp
index 91ed10ca..793b7a90 100644
--- a/include/multigrid_pclomp/multigrid_ndt_omp_impl.hpp
+++ b/include/multigrid_pclomp/multigrid_ndt_omp_impl.hpp
@@ -582,11 +582,11 @@ double pclomp::MultiGridNormalDistributionsTransform<PointSource, PointTarget>::
     for(int i = 0; i < 6; ++i) {
       // Sigma_k^-1 d(T(x,p))/dpi, Reusable portion of Equation 6.12 and 6.13 [Magnusson 2009]
       // Update gradient, Equation 6.12 [Magnusson 2009]
-      x_trans4_dot_c_inv4_x_ext_point_hessian_4ij.noalias() = x_trans4_x_c_inv4 * point_hessian_.block<4, 6>(i * 4, 0);
+      x_trans4_dot_c_inv4_x_ext_point_hessian4ij.noalias() = x_trans4_x_c_inv4 * point_hessian.block<4, 6>(i * 4, 0);
 
       for(int j = 0; j < hessian.cols(); j++) {
         // Update hessian, Equation 6.13 [Magnusson 2009]
-        hessian(i, j) += e_x_cov_x * (-gauss_d2 * x_trans4_dot_c_inv4_x_point_gradient4(i) * x_trans4_dot_c_inv4_x_point_gradient4(j) + x_trans4_dot_c_inv4_x_ext_point_hessian_4ij(j) + point_gradient4_colj_dot_c_inv4_x_point_gradient4_col_i(j, i));
+        hessian(i, j) += e_x_cov_x * (-gauss_d2 * x_trans4_dot_c_inv4_x_point_gradient4(i) * x_trans4_dot_c_inv4_x_point_gradient4(j) + x_trans4_dot_c_inv4_x_ext_point_hessian4ij(j) + point_gradient4_colj_dot_c_inv4_x_point_gradient4_col_i(j, i));
       }
     }
   }