diff --git a/dune/tectonic/myblockproblem.hh b/dune/tectonic/myblockproblem.hh
index f79ee7b212d681c64e14bf2963e09c06710fec59..70f7058198abc286049ebe158ce41883c5662091 100644
--- a/dune/tectonic/myblockproblem.hh
+++ b/dune/tectonic/myblockproblem.hh
@@ -140,16 +140,16 @@ template <class MyConvexProblemTypeTEMPLATE> class MyBlockProblem {
       it = linearization.A[row].begin();
       end = linearization.A[row].end();
       for (; it != end; ++it) {
-        int col = it.index();
-        for (int i = 0; i < (*it).N(); ++i) {
+        int const col = it.index();
+        for (int i = 0; i < it->N(); ++i) {
           typename Linearization::MatrixType::block_type::row_type::Iterator
           blockIt = (*it)[i].begin();
-          typename Linearization::MatrixType::block_type::row_type::Iterator
-          blockEnd = (*it)[i].end();
+          typename Linearization::MatrixType::block_type::row_type::
+              Iterator const blockEnd = (*it)[i].end();
           for (; blockIt != blockEnd; ++blockIt)
             if (linearization.truncation[row][i] or linearization
                     .truncation[col][blockIt.index()])
-              (*blockIt) = 0.0;
+              *blockIt = 0.0;
         }
       }