diff --git a/src/test-gradient-horrible-logarithmic.cc b/src/test-gradient-horrible-logarithmic.cc
index 6991b3000e8491ee4c463707ccfe60c9ed0fb90a..9507dcfe119b56509a4d583120823327c6528ce2 100644
--- a/src/test-gradient-horrible-logarithmic.cc
+++ b/src/test-gradient-horrible-logarithmic.cc
@@ -27,8 +27,8 @@ int main() {
   b[0] = 1;
   b[1] = 2;
 
-  auto f = Dune::make_shared<Dune::HorribleFunctionLogarithmic const>();
-  auto phi = Dune::make_shared<Functional::NonlinearityType const>(f);
+  auto const f = Dune::make_shared<Dune::HorribleFunctionLogarithmic const>();
+  auto const phi = Dune::make_shared<Functional::NonlinearityType const>(f);
   Functional J(A, b, phi);
 
   SmallVector start = b;
diff --git a/src/test-gradient-horrible.cc b/src/test-gradient-horrible.cc
index 55dad1448c1ee2069624ae5da3c9f2e4c088ea54..e3215d00dd731da612f1691304c1fb849e82242c 100644
--- a/src/test-gradient-horrible.cc
+++ b/src/test-gradient-horrible.cc
@@ -27,8 +27,8 @@ int main() {
   b[0] = 1;
   b[1] = 2;
 
-  auto f = Dune::make_shared<Dune::HorribleFunction const>();
-  auto phi = Dune::make_shared<Functional::NonlinearityType const>(f);
+  auto const f = Dune::make_shared<Dune::HorribleFunction const>();
+  auto const phi = Dune::make_shared<Functional::NonlinearityType const>(f);
   Functional J(A, b, phi);
 
   SmallVector start = b;
diff --git a/src/test-gradient-identity.cc b/src/test-gradient-identity.cc
index fb5887a1cd74213e93bc33d985341153dc5b59b0..82eac754f845540985128c4c22ffff611a41cc70 100644
--- a/src/test-gradient-identity.cc
+++ b/src/test-gradient-identity.cc
@@ -27,8 +27,8 @@ int main() {
   b[0] = 1;
   b[1] = 2;
 
-  auto f = Dune::make_shared<Dune::LinearFunction const>(1);
-  auto phi = Dune::make_shared<Functional::NonlinearityType const>(f);
+  auto const f = Dune::make_shared<Dune::LinearFunction const>(1);
+  auto const phi = Dune::make_shared<Functional::NonlinearityType const>(f);
   Functional J(A, b, phi);
 
   SmallVector start = b;
diff --git a/src/test-gradient-parabola.cc b/src/test-gradient-parabola.cc
index 52b089ce3038350910035b8a2ab7ccd01f81a13f..cce5f56b5f07e55a381a47f3bd71000278410ed6 100644
--- a/src/test-gradient-parabola.cc
+++ b/src/test-gradient-parabola.cc
@@ -32,8 +32,8 @@ int main() {
   // |x|^2 as the nonlinearity is the same as having no nonlinearity
   // but twice the identity matrix added to A. In other words, we're
   // solving A + 2*id = b
-  auto f = Dune::make_shared<Dune::Parabola const>();
-  auto phi = Dune::make_shared<Functional::NonlinearityType const>(f);
+  auto const f = Dune::make_shared<Dune::Parabola const>();
+  auto const phi = Dune::make_shared<Functional::NonlinearityType const>(f);
   Functional J(A, b, phi);
 
   SmallVector solution; // Analytic solution
diff --git a/src/test-gradient-sample-3d.cc b/src/test-gradient-sample-3d.cc
index a6e7578edda0b4bcf05949637ec90982d1e21ab0..ae2cb3e095b8bcd0981439461e2ea4bc46e0acd6 100644
--- a/src/test-gradient-sample-3d.cc
+++ b/src/test-gradient-sample-3d.cc
@@ -30,8 +30,8 @@ int main() {
   b[1] = 2;
   b[2] = 3;
 
-  auto f = Dune::make_shared<Dune::SampleFunction<2> const>();
-  auto phi = Dune::make_shared<Functional::NonlinearityType const>(f);
+  auto const f = Dune::make_shared<Dune::SampleFunction<2> const>();
+  auto const phi = Dune::make_shared<Functional::NonlinearityType const>(f);
   Functional J(A, b, phi);
 
   SmallVector start = b;
diff --git a/src/test-gradient-sample-nonsmooth.cc b/src/test-gradient-sample-nonsmooth.cc
index 5b2375194c3c55dbd1a2651ba1337ff04a6a3ec0..e8f49226e4832dd5c3e90fff8d119601356c610e 100644
--- a/src/test-gradient-sample-nonsmooth.cc
+++ b/src/test-gradient-sample-nonsmooth.cc
@@ -28,8 +28,8 @@ int main() {
   b[0] = 1;
   b[1] = 2;
 
-  auto f = Dune::make_shared<Dune::SampleFunction<2> const>();
-  auto phi = Dune::make_shared<Functional::NonlinearityType const>(f);
+  auto const f = Dune::make_shared<Dune::SampleFunction<2> const>();
+  auto const phi = Dune::make_shared<Functional::NonlinearityType const>(f);
   Functional J(A, b, phi);
 
   SmallVector start;
diff --git a/src/test-gradient-sample-steep.cc b/src/test-gradient-sample-steep.cc
index f636de243d262bed21c81dc043e308a36d061de2..3cd290dd0149b5d3bb945e8b123d923705a4e5e1 100644
--- a/src/test-gradient-sample-steep.cc
+++ b/src/test-gradient-sample-steep.cc
@@ -27,8 +27,8 @@ int main() {
   b[0] = 1;
   b[1] = 2;
 
-  auto f = Dune::make_shared<Dune::SampleFunction<2> const>();
-  auto phi = Dune::make_shared<Functional::NonlinearityType const>(f);
+  auto const f = Dune::make_shared<Dune::SampleFunction<2> const>();
+  auto const phi = Dune::make_shared<Functional::NonlinearityType const>(f);
   Functional J(A, b, phi);
 
   SmallVector start;
diff --git a/src/test-gradient-sample-steep2.cc b/src/test-gradient-sample-steep2.cc
index cd8a074e4faae32b0d9e32eb464efeb109b9fea0..abbd289901d238822d2fdb8501a8e42f494498e9 100644
--- a/src/test-gradient-sample-steep2.cc
+++ b/src/test-gradient-sample-steep2.cc
@@ -27,8 +27,8 @@ int main() {
   b[0] = 1;
   b[1] = 2.5;
 
-  auto f = Dune::make_shared<Dune::SampleFunction<2> const>();
-  auto phi = Dune::make_shared<Functional::NonlinearityType const>(f);
+  auto const f = Dune::make_shared<Dune::SampleFunction<2> const>();
+  auto const phi = Dune::make_shared<Functional::NonlinearityType const>(f);
   Functional J(A, b, phi);
 
   SmallVector start;
diff --git a/src/test-gradient-sample-verysteep.cc b/src/test-gradient-sample-verysteep.cc
index 74d2bd3d38cf94e601f058a594276c366ba852c0..12fd5c3d9d9baa19008b03adcf24af167803055d 100644
--- a/src/test-gradient-sample-verysteep.cc
+++ b/src/test-gradient-sample-verysteep.cc
@@ -27,8 +27,8 @@ int main() {
   b[0] = 1;
   b[1] = 2.5;
 
-  auto f = Dune::make_shared<Dune::SampleFunction<100> const>();
-  auto phi = Dune::make_shared<Functional::NonlinearityType const>(f);
+  auto const f = Dune::make_shared<Dune::SampleFunction<100> const>();
+  auto const phi = Dune::make_shared<Functional::NonlinearityType const>(f);
   Functional J(A, b, phi);
 
   SmallVector start;
diff --git a/src/test-gradient-sample.cc b/src/test-gradient-sample.cc
index 3d09b7a71ff4df75cf464e37f1aefd5ace8c2bc4..e10acc130a751ad0e89b097c85c11277843c7ff3 100644
--- a/src/test-gradient-sample.cc
+++ b/src/test-gradient-sample.cc
@@ -29,8 +29,8 @@ int main() {
   b[0] = 1;
   b[1] = 2;
 
-  auto f = Dune::make_shared<Dune::SampleFunction<2> const>();
-  auto phi = Dune::make_shared<Functional::NonlinearityType const>(f);
+  auto const f = Dune::make_shared<Dune::SampleFunction<2> const>();
+  auto const phi = Dune::make_shared<Functional::NonlinearityType const>(f);
   Functional J(A, b, phi);
 
   SmallVector start = b;
diff --git a/src/test-gradient-sample2.cc b/src/test-gradient-sample2.cc
index 1392cad6fe29745969b88fd43c68d1744bbc654c..9bbd7ec476e9bf32ed9fb655df05b23b70b68989 100644
--- a/src/test-gradient-sample2.cc
+++ b/src/test-gradient-sample2.cc
@@ -29,8 +29,8 @@ int main() {
   b[0] = 1;
   b[1] = 1;
 
-  auto f = Dune::make_shared<Dune::SampleFunction<2> const>();
-  auto phi = Dune::make_shared<Functional::NonlinearityType const>(f);
+  auto const f = Dune::make_shared<Dune::SampleFunction<2> const>();
+  auto const phi = Dune::make_shared<Functional::NonlinearityType const>(f);
   Functional J(A, b, phi);
 
   SmallVector start = b;
diff --git a/src/test-gradient-trivial.cc b/src/test-gradient-trivial.cc
index 1e4b4cc5c4bed4e18e534fbb10647bc1bb56c981..2718dbe2313b0a44f55e33e07ab4e94e91849319 100644
--- a/src/test-gradient-trivial.cc
+++ b/src/test-gradient-trivial.cc
@@ -28,8 +28,8 @@ int main() {
   b[0] = 1;
   b[1] = 2;
 
-  auto f = Dune::make_shared<Dune::TrivialFunction const>();
-  auto phi = Dune::make_shared<Functional::NonlinearityType const>(f);
+  auto const f = Dune::make_shared<Dune::TrivialFunction const>();
+  auto const phi = Dune::make_shared<Functional::NonlinearityType const>(f);
   Functional J(A, b, phi);
 
   SmallVector solution; // Analytic solution