diff --git a/Documentation/Tutorials/ReductionAndScan/ExclusiveScanExample.cpp b/Documentation/Tutorials/ReductionAndScan/ExclusiveScanExample.cpp
index 0277ad9a43f974894e0cf7e38ee4cbf554d06511..9ccb5baa86c26dabb155226207b6dfd551c595dc 100644
--- a/Documentation/Tutorials/ReductionAndScan/ExclusiveScanExample.cpp
+++ b/Documentation/Tutorials/ReductionAndScan/ExclusiveScanExample.cpp
@@ -1,10 +1,6 @@
 #include <iostream>
 #include <cstdlib>
 #include <TNL/Containers/Vector.h>
-#include <TNL/Containers/Array.h>
-#include <TNL/Containers/Algorithms/Reduction.h>
-
-#include <TNL/Containers/StaticVector.h>
 
 using namespace TNL;
 using namespace TNL::Containers;
diff --git a/Documentation/Tutorials/ReductionAndScan/MapReduceExample-1.cpp b/Documentation/Tutorials/ReductionAndScan/MapReduceExample-1.cpp
index 419607f05676ba159a42d2969a49e185fa02443a..8d21107fdc444872783c057a329f5c812f83527e 100644
--- a/Documentation/Tutorials/ReductionAndScan/MapReduceExample-1.cpp
+++ b/Documentation/Tutorials/ReductionAndScan/MapReduceExample-1.cpp
@@ -2,7 +2,6 @@
 #include <cstdlib>
 #include <TNL/Containers/Vector.h>
 #include <TNL/Containers/Algorithms/Reduction.h>
-#include <TNL/Timer.h>
 
 using namespace TNL;
 using namespace TNL::Containers;
@@ -20,7 +19,6 @@ double mapReduce( Vector< double, Device >& u )
 
 int main( int argc, char* argv[] )
 {
-   Timer timer;
    Vector< double, Devices::Host > host_u( 10 );
    host_u.evaluate( [] __cuda_callable__ ( int i ) { return sin( ( double ) i ); } );
    double result = mapReduce( host_u );
diff --git a/Documentation/Tutorials/ReductionAndScan/ScanExample.cpp b/Documentation/Tutorials/ReductionAndScan/ScanExample.cpp
index 4f7c990e7e89cd13775e8b60d7176a16ee3da3cf..38f44ccddac7eea5a92395180804ebefb1bef17b 100644
--- a/Documentation/Tutorials/ReductionAndScan/ScanExample.cpp
+++ b/Documentation/Tutorials/ReductionAndScan/ScanExample.cpp
@@ -1,10 +1,6 @@
 #include <iostream>
 #include <cstdlib>
 #include <TNL/Containers/Vector.h>
-#include <TNL/Containers/Array.h>
-#include <TNL/Containers/Algorithms/Reduction.h>
-
-#include <TNL/Containers/StaticVector.h>
 
 using namespace TNL;
 using namespace TNL::Containers;
diff --git a/Documentation/Tutorials/ReductionAndScan/SegmentedScanExample.cpp b/Documentation/Tutorials/ReductionAndScan/SegmentedScanExample.cpp
index 607757e89a929022954aecf0a7f07ea8f7003a54..b3f67763906d7770cb65cf36a637eb0379928736 100644
--- a/Documentation/Tutorials/ReductionAndScan/SegmentedScanExample.cpp
+++ b/Documentation/Tutorials/ReductionAndScan/SegmentedScanExample.cpp
@@ -1,10 +1,6 @@
 #include <iostream>
 #include <cstdlib>
 #include <TNL/Containers/Vector.h>
-#include <TNL/Containers/Array.h>
-#include <TNL/Containers/Algorithms/Reduction.h>
-
-#include <TNL/Containers/StaticVector.h>
 
 using namespace TNL;
 using namespace TNL::Containers;
diff --git a/Documentation/Tutorials/ReductionAndScan/SequentialSumWithLambdas.cpp b/Documentation/Tutorials/ReductionAndScan/SequentialSumWithLambdas.cpp
index 7990faee581b903a3fed2704b0822e1da13aa568..0932b8b181fda7646937afb3102a5ea2601b0a2c 100644
--- a/Documentation/Tutorials/ReductionAndScan/SequentialSumWithLambdas.cpp
+++ b/Documentation/Tutorials/ReductionAndScan/SequentialSumWithLambdas.cpp
@@ -1,11 +1,11 @@
 double sequentialSum( const double* a, const int size )
 {
    auto fetch = [=] (int i)->double { return a[ i ]; };
-   auto reduce = [] (double& x, const double& y) { x += y; };
+   auto reduce = [] (double& x, const double& y) { return x + y; };
 
    double sum( 0.0 );
    for( int i = 0; i < size; i++ )
-       reduce( sum, fetch( i ) );
+       sum = reduce( sum, fetch( i ) );
    return sum;
 }
 
diff --git a/Documentation/Tutorials/ReductionAndScan/SumExample.cpp b/Documentation/Tutorials/ReductionAndScan/SumExample.cpp
index 092fc4a94f831afe1d1ccc1d05e810556f279284..3be04bd9245c8aef312d421f2bb4d68e4aacbea2 100644
--- a/Documentation/Tutorials/ReductionAndScan/SumExample.cpp
+++ b/Documentation/Tutorials/ReductionAndScan/SumExample.cpp
@@ -1,11 +1,8 @@
 #include <iostream>
 #include <cstdlib>
 #include <TNL/Containers/Vector.h>
-#include <TNL/Containers/Array.h>
 #include <TNL/Containers/Algorithms/Reduction.h>
 
-#include <TNL/Containers/StaticVector.h>
-
 using namespace TNL;
 using namespace TNL::Containers;
 using namespace TNL::Containers::Algorithms;