diff --git a/dune/tectonic/nicefunction.hh b/dune/tectonic/nicefunction.hh
index 9561d5b561ce8c09f624381ceec72de6303aebb1..95289ddd30ac0dc22b9448fdb66ec478d827b12a 100644
--- a/dune/tectonic/nicefunction.hh
+++ b/dune/tectonic/nicefunction.hh
@@ -46,51 +46,51 @@ class RuinaFunction : public NiceFunction {
         a(a),
         V0(V0),
         coefficientProduct(coefficient * normalStress),
-        K(mu +
-          b * (state + std::log(V0 / L))), // state is assumed to be logarithmic
-        rho(std::exp(-K / a)) {}
+        // state is assumed to be logarithmic
+        K(mu + b * (state + std::log(V0 / L))),
+        V_m(std::exp(-K / a)) {}
 
-  double virtual evaluate(double x) const {
-    double const arg = x / V0;
-    if (arg <= rho)
+  double virtual evaluate(double V) const {
+    double const arg = V / V0;
+    if (arg <= V_m)
       return 0;
 
     return coefficientProduct *
-           (+a * arg * (std::log(arg) - 1) + K * arg + a * rho);
+           (+a * arg * (std::log(arg) - 1) + K * arg + a * V_m);
   }
 
-  double virtual leftDifferential(double x) const {
-    double const arg = x / V0;
-    if (arg <= rho)
+  double virtual leftDifferential(double V) const {
+    double const arg = V / V0;
+    if (arg <= V_m)
       return 0;
 
     double const ret = a * std::log(arg) + K;
     return coefficientProduct * ret;
   }
 
-  double virtual rightDifferential(double s) const {
-    return leftDifferential(s);
+  double virtual rightDifferential(double V) const {
+    return leftDifferential(V);
   }
 
-  double virtual second_deriv(double x) const {
-    assert(x >= 0);
+  double virtual second_deriv(double V) const {
+    assert(V >= 0);
     assert(V0 > 0);
-    double const arg = x / V0;
-    if (arg <= rho)
+    double const arg = V / V0;
+    if (arg <= V_m)
       return 0;
 
-    return coefficientProduct * a / x;
+    return coefficientProduct * a / V;
   }
 
-  double virtual regularity(double x) const {
-    assert(x >= 0);
+  double virtual regularity(double V) const {
+    assert(V >= 0);
     assert(V0 > 0);
-    double const arg = x / V0;
+    double const arg = V / V0;
     // TODO: Make this controllable
-    if (std::abs(arg - rho) < 1e-14)
+    if (std::abs(arg - V_m) < 1e-14)
       return std::numeric_limits<double>::infinity();
 
-    return std::abs(second_deriv(x));
+    return std::abs(second_deriv(V));
   }
 
   bool virtual smoothesNorm() const { return true; }
@@ -100,7 +100,7 @@ class RuinaFunction : public NiceFunction {
   double const V0;
   double const coefficientProduct;
   double const K;
-  double const rho;
+  double const V_m;
 };
 
 class TrivialFunction : public NiceFunction {