diff --git a/src/Examples/LinearAlgebra/VectorDataAccessor.cs b/src/Examples/LinearAlgebra/VectorDataAccessor.cs
index 9a1e1ebd..c19eeaf0 100644
--- a/src/Examples/LinearAlgebra/VectorDataAccessor.cs
+++ b/src/Examples/LinearAlgebra/VectorDataAccessor.cs
@@ -149,7 +149,7 @@ namespace Examples.LinearAlgebra
             Console.WriteLine(@"11. Enumerator usage");
             foreach (var value in vectorA.GetIndexedEnumerator())
             {
-                Console.WriteLine(@"Index = {0}; Value = {1}", value.Key, value.Value.ToString("#0.00\t", formatProvider));
+                Console.WriteLine(@"Index = {0}; Value = {1}", value.Item1, value.Item2.ToString("#0.00\t", formatProvider));
             }
 
             Console.WriteLine();
diff --git a/src/Numerics/LinearAlgebra/Complex/Solvers/Iterative/BiCgStab.cs b/src/Numerics/LinearAlgebra/Complex/Solvers/Iterative/BiCgStab.cs
index 14fe6014..b39dd009 100644
--- a/src/Numerics/LinearAlgebra/Complex/Solvers/Iterative/BiCgStab.cs
+++ b/src/Numerics/LinearAlgebra/Complex/Solvers/Iterative/BiCgStab.cs
@@ -528,7 +528,7 @@ namespace MathNet.Numerics.LinearAlgebra.Complex.Solvers.Iterative
                 var solution = Solve(matrix, (Vector)input.Column(column));
                 foreach (var element in solution.GetIndexedEnumerator())
                 {
-                    result.At(element.Key, column, element.Value);
+                    result.At(element.Item1, column, element.Item2);
                 }
             }
         }
diff --git a/src/Numerics/LinearAlgebra/Complex/Solvers/Iterative/CompositeSolver.cs b/src/Numerics/LinearAlgebra/Complex/Solvers/Iterative/CompositeSolver.cs
index 133c7325..9f6cb109 100644
--- a/src/Numerics/LinearAlgebra/Complex/Solvers/Iterative/CompositeSolver.cs
+++ b/src/Numerics/LinearAlgebra/Complex/Solvers/Iterative/CompositeSolver.cs
@@ -624,7 +624,7 @@ namespace MathNet.Numerics.LinearAlgebra.Complex.Solvers.Iterative
                 var solution = Solve(matrix, (Vector)input.Column(column));
                 foreach (var element in solution.GetIndexedEnumerator())
                 {
-                    result.At(element.Key, column, element.Value);
+                    result.At(element.Item1, column, element.Item2);
                 }
             }
         }
diff --git a/src/Numerics/LinearAlgebra/Complex/Solvers/Iterative/GpBiCg.cs b/src/Numerics/LinearAlgebra/Complex/Solvers/Iterative/GpBiCg.cs
index 53b7e650..e72ca2de 100644
--- a/src/Numerics/LinearAlgebra/Complex/Solvers/Iterative/GpBiCg.cs
+++ b/src/Numerics/LinearAlgebra/Complex/Solvers/Iterative/GpBiCg.cs
@@ -638,7 +638,7 @@ namespace MathNet.Numerics.LinearAlgebra.Complex.Solvers.Iterative
                 var solution = Solve(matrix, (Vector)input.Column(column));
                 foreach (var element in solution.GetIndexedEnumerator())
                 {
-                    result.At(element.Key, column, element.Value);
+                    result.At(element.Item1, column, element.Item2);
                 }
             }
         }
diff --git a/src/Numerics/LinearAlgebra/Complex/Solvers/Iterative/MlkBiCgStab.cs b/src/Numerics/LinearAlgebra/Complex/Solvers/Iterative/MlkBiCgStab.cs
index d0b086b7..022ac9d4 100644
--- a/src/Numerics/LinearAlgebra/Complex/Solvers/Iterative/MlkBiCgStab.cs
+++ b/src/Numerics/LinearAlgebra/Complex/Solvers/Iterative/MlkBiCgStab.cs
@@ -805,7 +805,7 @@ namespace MathNet.Numerics.LinearAlgebra.Complex.Solvers.Iterative
                 var solution = Solve(matrix, (Vector)input.Column(column));
                 foreach (var element in solution.GetIndexedEnumerator())
                 {
-                    result.At(element.Key, column, element.Value);
+                    result.At(element.Item1, column, element.Item2);
                 }
             }
         }
diff --git a/src/Numerics/LinearAlgebra/Complex/Solvers/Iterative/TFQMR.cs b/src/Numerics/LinearAlgebra/Complex/Solvers/Iterative/TFQMR.cs
index 4d024c83..a6115316 100644
--- a/src/Numerics/LinearAlgebra/Complex/Solvers/Iterative/TFQMR.cs
+++ b/src/Numerics/LinearAlgebra/Complex/Solvers/Iterative/TFQMR.cs
@@ -533,7 +533,7 @@ namespace MathNet.Numerics.LinearAlgebra.Complex.Solvers.Iterative
                 var solution = Solve(matrix, (Vector)input.Column(column));
                 foreach (var element in solution.GetIndexedEnumerator())
                 {
-                    result.At(element.Key, column, element.Value);
+                    result.At(element.Item1, column, element.Item2);
                 }
             }
         }
diff --git a/src/Numerics/LinearAlgebra/Complex/SparseVector.cs b/src/Numerics/LinearAlgebra/Complex/SparseVector.cs
index 64146344..4b740ff1 100644
--- a/src/Numerics/LinearAlgebra/Complex/SparseVector.cs
+++ b/src/Numerics/LinearAlgebra/Complex/SparseVector.cs
@@ -1326,16 +1326,16 @@ namespace MathNet.Numerics.LinearAlgebra.Complex
         /// </returns>
         /// <remarks>
         /// The enumerator returns a 
-        /// <seealso cref="KeyValuePair{T,K}"/>
-        /// with the key being the element index and the value 
+        /// <seealso cref="Tuple{T,K}"/>
+        /// with the first value being the element index and the second value 
         /// being the value of the element at that index. For sparse vectors, the enumerator will exclude all elements
         /// with a zero value.
         /// </remarks>
-        public override IEnumerable<KeyValuePair<int, Complex>> GetIndexedEnumerator()
+        public override IEnumerable<Tuple<int, Complex>> GetIndexedEnumerator()
         {
             for (var i = 0; i < NonZerosCount; i++)
             {
-                yield return new KeyValuePair<int, Complex>(_nonZeroIndices[i], _nonZeroValues[i]);
+                yield return new Tuple<int, Complex>(_nonZeroIndices[i], _nonZeroValues[i]);
             }
         }
 
diff --git a/src/Numerics/LinearAlgebra/Complex32/Solvers/Iterative/BiCgStab.cs b/src/Numerics/LinearAlgebra/Complex32/Solvers/Iterative/BiCgStab.cs
index b359f19d..2d7309c2 100644
--- a/src/Numerics/LinearAlgebra/Complex32/Solvers/Iterative/BiCgStab.cs
+++ b/src/Numerics/LinearAlgebra/Complex32/Solvers/Iterative/BiCgStab.cs
@@ -527,7 +527,7 @@ namespace MathNet.Numerics.LinearAlgebra.Complex32.Solvers.Iterative
                 var solution = Solve(matrix, (Vector)input.Column(column));
                 foreach (var element in solution.GetIndexedEnumerator())
                 {
-                    result.At(element.Key, column, element.Value);
+                    result.At(element.Item1, column, element.Item2);
                 }
             }
         }
diff --git a/src/Numerics/LinearAlgebra/Complex32/Solvers/Iterative/CompositeSolver.cs b/src/Numerics/LinearAlgebra/Complex32/Solvers/Iterative/CompositeSolver.cs
index 22f868cf..c4ec532a 100644
--- a/src/Numerics/LinearAlgebra/Complex32/Solvers/Iterative/CompositeSolver.cs
+++ b/src/Numerics/LinearAlgebra/Complex32/Solvers/Iterative/CompositeSolver.cs
@@ -621,7 +621,7 @@ namespace MathNet.Numerics.LinearAlgebra.Complex32.Solvers.Iterative
                 var solution = Solve(matrix, (Vector)input.Column(column));
                 foreach (var element in solution.GetIndexedEnumerator())
                 {
-                    result.At(element.Key, column, element.Value);
+                    result.At(element.Item1, column, element.Item2);
                 }
             }
         }
diff --git a/src/Numerics/LinearAlgebra/Complex32/Solvers/Iterative/GpBiCg.cs b/src/Numerics/LinearAlgebra/Complex32/Solvers/Iterative/GpBiCg.cs
index 5451a75b..7f9b2fe0 100644
--- a/src/Numerics/LinearAlgebra/Complex32/Solvers/Iterative/GpBiCg.cs
+++ b/src/Numerics/LinearAlgebra/Complex32/Solvers/Iterative/GpBiCg.cs
@@ -638,7 +638,7 @@ namespace MathNet.Numerics.LinearAlgebra.Complex32.Solvers.Iterative
                 var solution = Solve(matrix, (Vector)input.Column(column));
                 foreach (var element in solution.GetIndexedEnumerator())
                 {
-                    result.At(element.Key, column, element.Value);
+                    result.At(element.Item1, column, element.Item2);
                 }
             }
         }
diff --git a/src/Numerics/LinearAlgebra/Complex32/Solvers/Iterative/MlkBiCgStab.cs b/src/Numerics/LinearAlgebra/Complex32/Solvers/Iterative/MlkBiCgStab.cs
index ed1649e9..f7e311eb 100644
--- a/src/Numerics/LinearAlgebra/Complex32/Solvers/Iterative/MlkBiCgStab.cs
+++ b/src/Numerics/LinearAlgebra/Complex32/Solvers/Iterative/MlkBiCgStab.cs
@@ -804,7 +804,7 @@ namespace MathNet.Numerics.LinearAlgebra.Complex32.Solvers.Iterative
                 var solution = Solve(matrix, (Vector)input.Column(column));
                 foreach (var element in solution.GetIndexedEnumerator())
                 {
-                    result.At(element.Key, column, element.Value);
+                    result.At(element.Item1, column, element.Item2);
                 }
             }
         }
diff --git a/src/Numerics/LinearAlgebra/Complex32/Solvers/Iterative/TFQMR.cs b/src/Numerics/LinearAlgebra/Complex32/Solvers/Iterative/TFQMR.cs
index 06af4ffd..fed7f844 100644
--- a/src/Numerics/LinearAlgebra/Complex32/Solvers/Iterative/TFQMR.cs
+++ b/src/Numerics/LinearAlgebra/Complex32/Solvers/Iterative/TFQMR.cs
@@ -533,7 +533,7 @@ namespace MathNet.Numerics.LinearAlgebra.Complex32.Solvers.Iterative
                 var solution = Solve(matrix, (Vector)input.Column(column));
                 foreach (var element in solution.GetIndexedEnumerator())
                 {
-                    result.At(element.Key, column, element.Value);
+                    result.At(element.Item1, column, element.Item2);
                 }
             }
         }
diff --git a/src/Numerics/LinearAlgebra/Complex32/SparseVector.cs b/src/Numerics/LinearAlgebra/Complex32/SparseVector.cs
index 991f32c8..40c5ff7d 100644
--- a/src/Numerics/LinearAlgebra/Complex32/SparseVector.cs
+++ b/src/Numerics/LinearAlgebra/Complex32/SparseVector.cs
@@ -1356,16 +1356,16 @@ namespace MathNet.Numerics.LinearAlgebra.Complex32
         /// </returns>
         /// <remarks>
         /// The enumerator returns a 
-        /// <seealso cref="KeyValuePair{T,K}"/>
-        /// with the key being the element index and the value 
+        /// <seealso cref="Tuple{T,K}"/>
+        /// with the first value being the element index and the second value 
         /// being the value of the element at that index. For sparse vectors, the enumerator will exclude all elements
         /// with a zero value.
         /// </remarks>
-        public override IEnumerable<KeyValuePair<int, Complex32>> GetIndexedEnumerator()
+        public override IEnumerable<Tuple<int, Complex32>> GetIndexedEnumerator()
         {
             for (var i = 0; i < NonZerosCount; i++)
             {
-                yield return new KeyValuePair<int, Complex32>(_nonZeroIndices[i], _nonZeroValues[i]);
+                yield return new Tuple<int, Complex32>(_nonZeroIndices[i], _nonZeroValues[i]);
             }
         }
 
diff --git a/src/Numerics/LinearAlgebra/Double/Solvers/Iterative/BiCgStab.cs b/src/Numerics/LinearAlgebra/Double/Solvers/Iterative/BiCgStab.cs
index 7fcb67de..9bf21fca 100644
--- a/src/Numerics/LinearAlgebra/Double/Solvers/Iterative/BiCgStab.cs
+++ b/src/Numerics/LinearAlgebra/Double/Solvers/Iterative/BiCgStab.cs
@@ -526,7 +526,7 @@ namespace MathNet.Numerics.LinearAlgebra.Double.Solvers.Iterative
                 var solution = Solve(matrix, (Vector)input.Column(column));
                 foreach (var element in solution.GetIndexedEnumerator())
                 {
-                    result.At(element.Key, column, element.Value);
+                    result.At(element.Item1, column, element.Item2);
                 }
             }
         }
diff --git a/src/Numerics/LinearAlgebra/Double/Solvers/Iterative/CompositeSolver.cs b/src/Numerics/LinearAlgebra/Double/Solvers/Iterative/CompositeSolver.cs
index dd9bddb1..f3b8f902 100644
--- a/src/Numerics/LinearAlgebra/Double/Solvers/Iterative/CompositeSolver.cs
+++ b/src/Numerics/LinearAlgebra/Double/Solvers/Iterative/CompositeSolver.cs
@@ -619,7 +619,7 @@ namespace MathNet.Numerics.LinearAlgebra.Double.Solvers.Iterative
                 var solution = Solve(matrix, (Vector)input.Column(column));
                 foreach (var element in solution.GetIndexedEnumerator())
                 {
-                    result.At(element.Key, column, element.Value);
+                    result.At(element.Item1, column, element.Item2);
                 }
             }
         }
diff --git a/src/Numerics/LinearAlgebra/Double/Solvers/Iterative/GpBiCg.cs b/src/Numerics/LinearAlgebra/Double/Solvers/Iterative/GpBiCg.cs
index 40241d64..f85d2c49 100644
--- a/src/Numerics/LinearAlgebra/Double/Solvers/Iterative/GpBiCg.cs
+++ b/src/Numerics/LinearAlgebra/Double/Solvers/Iterative/GpBiCg.cs
@@ -637,7 +637,7 @@ namespace MathNet.Numerics.LinearAlgebra.Double.Solvers.Iterative
                 var solution = Solve(matrix, (Vector)input.Column(column));
                 foreach (var element in solution.GetIndexedEnumerator())
                 {
-                    result.At(element.Key, column, element.Value);
+                    result.At(element.Item1, column, element.Item2);
                 }
             }
         }
diff --git a/src/Numerics/LinearAlgebra/Double/Solvers/Iterative/MlkBiCgStab.cs b/src/Numerics/LinearAlgebra/Double/Solvers/Iterative/MlkBiCgStab.cs
index a87e5046..b2090c1a 100644
--- a/src/Numerics/LinearAlgebra/Double/Solvers/Iterative/MlkBiCgStab.cs
+++ b/src/Numerics/LinearAlgebra/Double/Solvers/Iterative/MlkBiCgStab.cs
@@ -798,7 +798,7 @@ namespace MathNet.Numerics.LinearAlgebra.Double.Solvers.Iterative
                 var solution = Solve(matrix, (Vector)input.Column(column));
                 foreach (var element in solution.GetIndexedEnumerator())
                 {
-                    result.At(element.Key, column, element.Value);
+                    result.At(element.Item1, column, element.Item2);
                 }
             }
         }
diff --git a/src/Numerics/LinearAlgebra/Double/Solvers/Iterative/TFQMR.cs b/src/Numerics/LinearAlgebra/Double/Solvers/Iterative/TFQMR.cs
index 02d68401..e122a3f5 100644
--- a/src/Numerics/LinearAlgebra/Double/Solvers/Iterative/TFQMR.cs
+++ b/src/Numerics/LinearAlgebra/Double/Solvers/Iterative/TFQMR.cs
@@ -532,7 +532,7 @@ namespace MathNet.Numerics.LinearAlgebra.Double.Solvers.Iterative
                 var solution = Solve(matrix, (Vector)input.Column(column));
                 foreach (var element in solution.GetIndexedEnumerator())
                 {
-                    result.At(element.Key, column, element.Value);
+                    result.At(element.Item1, column, element.Item2);
                 }
             }
         }
diff --git a/src/Numerics/LinearAlgebra/Double/SparseVector.cs b/src/Numerics/LinearAlgebra/Double/SparseVector.cs
index b8be1d2a..f2def50e 100644
--- a/src/Numerics/LinearAlgebra/Double/SparseVector.cs
+++ b/src/Numerics/LinearAlgebra/Double/SparseVector.cs
@@ -1361,16 +1361,16 @@ namespace MathNet.Numerics.LinearAlgebra.Double
         /// </returns>
         /// <remarks>
         /// The enumerator returns a 
-        /// <seealso cref="KeyValuePair{T,K}"/>
-        /// with the key being the element index and the value 
+        /// <seealso cref="Tuple{T,K}"/>
+        /// with the first value being the element index and the second value 
         /// being the value of the element at that index. For sparse vectors, the enumerator will exclude all elements
         /// with a zero value.
         /// </remarks>
-        public override IEnumerable<KeyValuePair<int, double>> GetIndexedEnumerator()
+        public override IEnumerable<Tuple<int, double>> GetIndexedEnumerator()
         {
             for (var i = 0; i < NonZerosCount; i++)
             {
-                yield return new KeyValuePair<int, double>(_nonZeroIndices[i], _nonZeroValues[i]);
+                yield return new Tuple<int, double>(_nonZeroIndices[i], _nonZeroValues[i]);
             }
         }
 
diff --git a/src/Numerics/LinearAlgebra/Generic/Matrix.cs b/src/Numerics/LinearAlgebra/Generic/Matrix.cs
index 39a4409c..f98ff2a9 100644
--- a/src/Numerics/LinearAlgebra/Generic/Matrix.cs
+++ b/src/Numerics/LinearAlgebra/Generic/Matrix.cs
@@ -1253,7 +1253,7 @@ namespace MathNet.Numerics.LinearAlgebra.Generic
                 var columnIndex = column.Key * RowCount;
                 foreach (var element in column.Value.GetIndexedEnumerator())
                 {
-                    ret[columnIndex + element.Key] = element.Value;
+                    ret[columnIndex + element.Item1] = element.Item2;
                 }
             }
 
@@ -1278,7 +1278,7 @@ namespace MathNet.Numerics.LinearAlgebra.Generic
                 var rowIndex = row.Key * ColumnCount;
                 foreach (var element in row.Value.GetIndexedEnumerator())
                 {
-                    ret[rowIndex + element.Key] = element.Value;
+                    ret[rowIndex + element.Item1] = element.Item2;
                 }
             }
 
diff --git a/src/Numerics/LinearAlgebra/Generic/Vector.cs b/src/Numerics/LinearAlgebra/Generic/Vector.cs
index 7d9fcd76..d5d70e0a 100644
--- a/src/Numerics/LinearAlgebra/Generic/Vector.cs
+++ b/src/Numerics/LinearAlgebra/Generic/Vector.cs
@@ -731,7 +731,12 @@ namespace MathNet.Numerics.LinearAlgebra.Generic
         /// <summary>
         /// Pointwise divide this vector with another vector and stores the result into the result vector.
         /// </summary>
-        /// <param name="other">The vector to pointwise divide this one by.</param>
+        /// <param name="other">
+        /// The vector to pointwise divide this one by.
+        /// </param>
+        /// <param name="result">
+        /// The result of the division.
+        /// </param>
         protected abstract void DoPointwiseDivide(Vector<T> other, Vector<T> result);
 
         /// <summary>
@@ -1389,16 +1394,16 @@ namespace MathNet.Numerics.LinearAlgebra.Generic
         /// </returns>
         /// <remarks>
         /// The enumerator returns a 
-        /// <seealso cref="KeyValuePair{T,K}"/>
-        /// with the key being the element index and the value 
+        /// <seealso cref="Tuple{T,K}"/>
+        /// with the first value being the element index and the second value 
         /// being the value of the element at that index. For sparse vectors, the enumerator will exclude all elements
         /// with a zero value.
         /// </remarks>
-        public virtual IEnumerable<KeyValuePair<int, T>> GetIndexedEnumerator()
+        public virtual IEnumerable<Tuple<int, T>> GetIndexedEnumerator()
         {
             for (var i = 0; i < Count; i++)
             {
-                yield return new KeyValuePair<int, T>(i, this[i]);
+                yield return new Tuple<int, T>(i, this[i]);
             }
         }
 
diff --git a/src/Numerics/LinearAlgebra/IO/MatlabWriter.cs b/src/Numerics/LinearAlgebra/IO/MatlabWriter.cs
index f3de218f..fc6292bd 100644
--- a/src/Numerics/LinearAlgebra/IO/MatlabWriter.cs
+++ b/src/Numerics/LinearAlgebra/IO/MatlabWriter.cs
@@ -483,7 +483,7 @@ namespace MathNet.Numerics.LinearAlgebra.IO
                 {
                     foreach (var row in column.Value.GetIndexedEnumerator())
                     {
-                        dataWriter.Write(row.Key);
+                        dataWriter.Write(row.Item1);
                     }
                 }
 
@@ -518,7 +518,7 @@ namespace MathNet.Numerics.LinearAlgebra.IO
                 {
                     foreach (var row in column.Value.GetIndexedEnumerator())
                     {
-                        dataWriter.Write(row.Value);
+                        dataWriter.Write(row.Item2);
                     }
                 }
 
@@ -551,7 +551,7 @@ namespace MathNet.Numerics.LinearAlgebra.IO
                 {
                     foreach (var row in column.Value.GetIndexedEnumerator())
                     {
-                        dataWriter.Write(row.Key);
+                        dataWriter.Write(row.Item1);
                     }
                 }
 
@@ -586,7 +586,7 @@ namespace MathNet.Numerics.LinearAlgebra.IO
                 {
                     foreach (var row in column.Value.GetIndexedEnumerator())
                     {
-                        dataWriter.Write(row.Value);
+                        dataWriter.Write(row.Item2);
                     }
                 }
 
@@ -622,7 +622,7 @@ namespace MathNet.Numerics.LinearAlgebra.IO
                 {
                     foreach (var row in column.Value.GetIndexedEnumerator())
                     {
-                        dataWriter.Write(row.Key);
+                        dataWriter.Write(row.Item1);
                     }
                 }
 
@@ -657,7 +657,7 @@ namespace MathNet.Numerics.LinearAlgebra.IO
                 {
                     foreach (var row in column.Value.GetIndexedEnumerator())
                     {
-                        dataWriter.Write(row.Value.Real);
+                        dataWriter.Write(row.Item2.Real);
                     }
                 }
 
@@ -668,7 +668,7 @@ namespace MathNet.Numerics.LinearAlgebra.IO
                 {
                     foreach (var row in column.Value.GetIndexedEnumerator())
                     {
-                        dataWriter.Write(row.Value.Real);
+                        dataWriter.Write(row.Item2.Real);
                     }
                 }
 
@@ -701,7 +701,7 @@ namespace MathNet.Numerics.LinearAlgebra.IO
                 {
                     foreach (var row in column.Value.GetIndexedEnumerator())
                     {
-                        dataWriter.Write(row.Key);
+                        dataWriter.Write(row.Item1);
                     }
                 }
 
@@ -736,7 +736,7 @@ namespace MathNet.Numerics.LinearAlgebra.IO
                 {
                     foreach (var row in column.Value.GetIndexedEnumerator())
                     {
-                        dataWriter.Write(row.Value.Real);
+                        dataWriter.Write(row.Item2.Real);
                     }
                 }
 
@@ -750,7 +750,7 @@ namespace MathNet.Numerics.LinearAlgebra.IO
                 {
                     foreach (var row in column.Value.GetIndexedEnumerator())
                     {
-                        dataWriter.Write(row.Value.Real);
+                        dataWriter.Write(row.Item2.Real);
                     }
                 }
 
diff --git a/src/Numerics/LinearAlgebra/Single/Solvers/Iterative/BiCgStab.cs b/src/Numerics/LinearAlgebra/Single/Solvers/Iterative/BiCgStab.cs
index 712c6548..26c6aaf9 100644
--- a/src/Numerics/LinearAlgebra/Single/Solvers/Iterative/BiCgStab.cs
+++ b/src/Numerics/LinearAlgebra/Single/Solvers/Iterative/BiCgStab.cs
@@ -526,7 +526,7 @@ namespace MathNet.Numerics.LinearAlgebra.Single.Solvers.Iterative
                 var solution = Solve(matrix, (Vector)input.Column(column));
                 foreach (var element in solution.GetIndexedEnumerator())
                 {
-                    result.At(element.Key, column, element.Value);
+                    result.At(element.Item1, column, element.Item2);
                 }
             }
         }
diff --git a/src/Numerics/LinearAlgebra/Single/Solvers/Iterative/CompositeSolver.cs b/src/Numerics/LinearAlgebra/Single/Solvers/Iterative/CompositeSolver.cs
index 3252c28d..1f8cbb19 100644
--- a/src/Numerics/LinearAlgebra/Single/Solvers/Iterative/CompositeSolver.cs
+++ b/src/Numerics/LinearAlgebra/Single/Solvers/Iterative/CompositeSolver.cs
@@ -621,7 +621,7 @@ namespace MathNet.Numerics.LinearAlgebra.Single.Solvers.Iterative
                 var solution = Solve(matrix, (Vector)input.Column(column));
                 foreach (var element in solution.GetIndexedEnumerator())
                 {
-                    result.At(element.Key, column, element.Value);
+                    result.At(element.Item1, column, element.Item2);
                 }
             }
         }
diff --git a/src/Numerics/LinearAlgebra/Single/Solvers/Iterative/GpBiCg.cs b/src/Numerics/LinearAlgebra/Single/Solvers/Iterative/GpBiCg.cs
index b7f9a4d9..48951507 100644
--- a/src/Numerics/LinearAlgebra/Single/Solvers/Iterative/GpBiCg.cs
+++ b/src/Numerics/LinearAlgebra/Single/Solvers/Iterative/GpBiCg.cs
@@ -637,7 +637,7 @@ namespace MathNet.Numerics.LinearAlgebra.Single.Solvers.Iterative
                 var solution = Solve(matrix, (Vector)input.Column(column));
                 foreach (var element in solution.GetIndexedEnumerator())
                 {
-                    result.At(element.Key, column, element.Value);
+                    result.At(element.Item1, column, element.Item2);
                 }
             }
         }
diff --git a/src/Numerics/LinearAlgebra/Single/Solvers/Iterative/MlkBiCgStab.cs b/src/Numerics/LinearAlgebra/Single/Solvers/Iterative/MlkBiCgStab.cs
index 7da752d9..0eaae0c2 100644
--- a/src/Numerics/LinearAlgebra/Single/Solvers/Iterative/MlkBiCgStab.cs
+++ b/src/Numerics/LinearAlgebra/Single/Solvers/Iterative/MlkBiCgStab.cs
@@ -800,7 +800,7 @@ namespace MathNet.Numerics.LinearAlgebra.Single.Solvers.Iterative
                 var solution = Solve(matrix, (Vector)input.Column(column));
                 foreach (var element in solution.GetIndexedEnumerator())
                 {
-                    result.At(element.Key, column, element.Value);
+                    result.At(element.Item1, column, element.Item2);
                 }
             }
         }
diff --git a/src/Numerics/LinearAlgebra/Single/Solvers/Iterative/TFQMR.cs b/src/Numerics/LinearAlgebra/Single/Solvers/Iterative/TFQMR.cs
index f8d48d91..acbbffd6 100644
--- a/src/Numerics/LinearAlgebra/Single/Solvers/Iterative/TFQMR.cs
+++ b/src/Numerics/LinearAlgebra/Single/Solvers/Iterative/TFQMR.cs
@@ -532,7 +532,7 @@ namespace MathNet.Numerics.LinearAlgebra.Single.Solvers.Iterative
                 var solution = Solve(matrix, (Vector)input.Column(column));
                 foreach (var element in solution.GetIndexedEnumerator())
                 {
-                    result.At(element.Key, column, element.Value);
+                    result.At(element.Item1, column, element.Item2);
                 }
             }
         }
diff --git a/src/Numerics/LinearAlgebra/Single/SparseVector.cs b/src/Numerics/LinearAlgebra/Single/SparseVector.cs
index 142971aa..0ccfc7ab 100644
--- a/src/Numerics/LinearAlgebra/Single/SparseVector.cs
+++ b/src/Numerics/LinearAlgebra/Single/SparseVector.cs
@@ -1368,16 +1368,16 @@ namespace MathNet.Numerics.LinearAlgebra.Single
         /// </returns>
         /// <remarks>
         /// The enumerator returns a 
-        /// <seealso cref="KeyValuePair{T,K}"/>
-        /// with the key being the element index and the value 
+        /// <seealso cref="Tuple{T,K}"/>
+        /// with the first value being the element index and the second value 
         /// being the value of the element at that index. For sparse vectors, the enumerator will exclude all elements
         /// with a zero value.
         /// </remarks>
-        public override IEnumerable<KeyValuePair<int, float>> GetIndexedEnumerator()
+        public override IEnumerable<Tuple<int, float>> GetIndexedEnumerator()
         {
             for (var i = 0; i < NonZerosCount; i++)
             {
-                yield return new KeyValuePair<int, float>(_nonZeroIndices[i], _nonZeroValues[i]);
+                yield return new Tuple<int, float>(_nonZeroIndices[i], _nonZeroValues[i]);
             }
         }
 
diff --git a/src/UnitTests/LinearAlgebraTests/Complex/VectorTests.cs b/src/UnitTests/LinearAlgebraTests/Complex/VectorTests.cs
index 5e121ee5..278dbe53 100644
--- a/src/UnitTests/LinearAlgebraTests/Complex/VectorTests.cs
+++ b/src/UnitTests/LinearAlgebraTests/Complex/VectorTests.cs
@@ -240,7 +240,7 @@ namespace MathNet.Numerics.UnitTests.LinearAlgebraTests.Complex
             var vector = CreateVector(Data);
             foreach (var pair in vector.GetIndexedEnumerator())
             {
-                Assert.AreEqual(Data[pair.Key], pair.Value);
+                Assert.AreEqual(Data[pair.Item1], pair.Item2);
             }
         }
 
diff --git a/src/UnitTests/LinearAlgebraTests/Complex32/VectorTests.cs b/src/UnitTests/LinearAlgebraTests/Complex32/VectorTests.cs
index eeb459c6..964af4bc 100644
--- a/src/UnitTests/LinearAlgebraTests/Complex32/VectorTests.cs
+++ b/src/UnitTests/LinearAlgebraTests/Complex32/VectorTests.cs
@@ -240,7 +240,7 @@ namespace MathNet.Numerics.UnitTests.LinearAlgebraTests.Complex32
             var vector = CreateVector(Data);
             foreach (var pair in vector.GetIndexedEnumerator())
             {
-                Assert.AreEqual(Data[pair.Key], pair.Value);
+                Assert.AreEqual(Data[pair.Item1], pair.Item2);
             }
         }
 
diff --git a/src/UnitTests/LinearAlgebraTests/Double/VectorTests.cs b/src/UnitTests/LinearAlgebraTests/Double/VectorTests.cs
index 8b861a7a..6de63357 100644
--- a/src/UnitTests/LinearAlgebraTests/Double/VectorTests.cs
+++ b/src/UnitTests/LinearAlgebraTests/Double/VectorTests.cs
@@ -238,7 +238,7 @@ namespace MathNet.Numerics.UnitTests.LinearAlgebraTests.Double
             var vector = CreateVector(Data);
             foreach (var pair in vector.GetIndexedEnumerator())
             {
-                Assert.AreEqual(Data[pair.Key], pair.Value);
+                Assert.AreEqual(Data[pair.Item1], pair.Item2);
             }
         }
 
diff --git a/src/UnitTests/LinearAlgebraTests/Single/VectorTests.cs b/src/UnitTests/LinearAlgebraTests/Single/VectorTests.cs
index 091c9069..40ee40b7 100644
--- a/src/UnitTests/LinearAlgebraTests/Single/VectorTests.cs
+++ b/src/UnitTests/LinearAlgebraTests/Single/VectorTests.cs
@@ -238,7 +238,7 @@ namespace MathNet.Numerics.UnitTests.LinearAlgebraTests.Single
             var vector = CreateVector(Data);
             foreach (var pair in vector.GetIndexedEnumerator())
             {
-                Assert.AreEqual(Data[pair.Key], pair.Value);
+                Assert.AreEqual(Data[pair.Item1], pair.Item2);
             }
         }