diff --git a/Math/Matrix/LUDecomposition.php b/Math/Matrix/LUDecomposition.php
index 9dd99fe5f..920f5c7ab 100644
--- a/Math/Matrix/LUDecomposition.php
+++ b/Math/Matrix/LUDecomposition.php
@@ -87,15 +87,15 @@ class LUDecomposition
         $L = [[]];
 
         for ($i = 0; $i < $this->m; ++$i) {
-			for ($j = 0; $j < $this->n; ++$j) {
-				if ($i > $j) {
-					$L[$i][$j] = $this->LU[$i][$j];
-				} elseif ($i == $j) {
-					$L[$i][$j] = 1.0;
-				} else {
-					$L[$i][$j] = 0.0;
-				}
-			}
+            for ($j = 0; $j < $this->n; ++$j) {
+                if ($i > $j) {
+                    $L[$i][$j] = $this->LU[$i][$j];
+                } elseif ($i == $j) {
+                    $L[$i][$j] = 1.0;
+                } else {
+                    $L[$i][$j] = 0.0;
+                }
+            }
         }
         
         $matrix = new Matrix();
@@ -109,14 +109,14 @@ class LUDecomposition
         $U = [[]];
 
         for ($i = 0; $i < $this->n; ++$i) {
-			for ($j = 0; $j < $this->n; ++$j) {
-				if ($i <= $j) {
-					$U[$i][$j] = $this->LU[$i][$j];
-				} else {
-					$U[$i][$j] = 0.0;
-				}
-			}
-		}
+            for ($j = 0; $j < $this->n; ++$j) {
+                if ($i <= $j) {
+                    $U[$i][$j] = $this->LU[$i][$j];
+                } else {
+                    $U[$i][$j] = 0.0;
+                }
+            }
+        }
         
         $matrix = new Matrix();
         $matrix->setMatrix($U);
@@ -132,9 +132,9 @@ class LUDecomposition
     public function isNonsingular() : bool
     {
         for ($j = 0; $j < $this->n; ++$j) {
-			if ($this->LU[$j][$j] == 0) {
-				return false;
-			}
+            if ($this->LU[$j][$j] == 0) {
+                return false;
+            }
         }
         
         return true;
diff --git a/Math/Matrix/QRDecomposition.php b/Math/Matrix/QRDecomposition.php
index 5e38f25c1..068199f55 100644
--- a/Math/Matrix/QRDecomposition.php
+++ b/Math/Matrix/QRDecomposition.php
@@ -27,56 +27,56 @@ class QRDecomposition
     public function __construct(Matrix $M)
     {
         // Initialize.
-		$this->QR = $M->toArray();
-		$this->m  = $M->getRowDimension();
+        $this->QR = $M->toArray();
+        $this->m  = $M->getRowDimension();
         $this->n  = $M->getColumnDimension();
         
-		// Main loop.
-		for ($k = 0; $k < $this->n; ++$k) {
-			// Compute 2-norm of k-th column without under/overflow.
-			$nrm = 0.0;
-			for ($i = $k; $i < $this->m; ++$i) {
-				$nrm = hypo($nrm, $this->QR[$i][$k]);
+        // Main loop.
+        for ($k = 0; $k < $this->n; ++$k) {
+            // Compute 2-norm of k-th column without under/overflow.
+            $nrm = 0.0;
+            for ($i = $k; $i < $this->m; ++$i) {
+                $nrm = hypo($nrm, $this->QR[$i][$k]);
             }
                 
-			if ($nrm != 0.0) {
-				// Form k-th Householder vector.
-				if ($this->QR[$k][$k] < 0) {
-					$nrm = -$nrm;
+            if ($nrm != 0.0) {
+                // Form k-th Householder vector.
+                if ($this->QR[$k][$k] < 0) {
+                    $nrm = -$nrm;
                 }
                     
-				for ($i = $k; $i < $this->m; ++$i) {
-					$this->QR[$i][$k] /= $nrm;
+                for ($i = $k; $i < $this->m; ++$i) {
+                    $this->QR[$i][$k] /= $nrm;
                 }
                     
-				$this->QR[$k][$k] += 1.0;
-				// Apply transformation to remaining columns.
-				for ($j = $k+1; $j < $this->n; ++$j) {
+                $this->QR[$k][$k] += 1.0;
+                // Apply transformation to remaining columns.
+                for ($j = $k+1; $j < $this->n; ++$j) {
                     $s = 0.0;
-					for ($i = $k; $i < $this->m; ++$i) {
-						$s += $this->QR[$i][$k] * $this->QR[$i][$j];
+                    for ($i = $k; $i < $this->m; ++$i) {
+                        $s += $this->QR[$i][$k] * $this->QR[$i][$j];
                     }
                         
-					$s = -$s/$this->QR[$k][$k];
-					for ($i = $k; $i < $this->m; ++$i) {
-						$this->QR[$i][$j] += $s * $this->QR[$i][$k];
-					}
-				}
-			}
+                    $s = -$s/$this->QR[$k][$k];
+                    for ($i = $k; $i < $this->m; ++$i) {
+                        $this->QR[$i][$j] += $s * $this->QR[$i][$k];
+                    }
+                }
+            }
                 
             $this->Rdiag[$k] = -$nrm;
-		}
+        }
     }
 
     public function isFullRank() : bool
     {
         for ($j = 0; $j < $this->n; ++$j) {
-			if ($this->Rdiag[$j] == 0) {
-				return false;
-			}
+            if ($this->Rdiag[$j] == 0) {
+                return false;
+            }
         }
         
-		return true;
+        return true;
     }
 
     public function getH()
@@ -84,13 +84,13 @@ class QRDecomposition
         $H = [[]];
 
         for ($i = 0; $i < $this->m; ++$i) {
-			for ($j = 0; $j < $this->n; ++$j) {
-				if ($i >= $j) {
-					$H[$i][$j] = $this->QR[$i][$j];
-				} else {
-					$H[$i][$j] = 0.0;
-				}
-			}
+            for ($j = 0; $j < $this->n; ++$j) {
+                if ($i >= $j) {
+                    $H[$i][$j] = $this->QR[$i][$j];
+                } else {
+                    $H[$i][$j] = 0.0;
+                }
+            }
         }
         
         $matrix = new Matrix();
@@ -104,15 +104,15 @@ class QRDecomposition
         $R = [[]];
 
         for ($i = 0; $i < $this->n; ++$i) {
-			for ($j = 0; $j < $this->n; ++$j) {
-				if ($i < $j) {
-					$R[$i][$j] = $this->QR[$i][$j];
-				} elseif ($i == $j) {
-					$R[$i][$j] = $this->Rdiag[$i];
-				} else {
-					$R[$i][$j] = 0.0;
-				}
-			}
+            for ($j = 0; $j < $this->n; ++$j) {
+                if ($i < $j) {
+                    $R[$i][$j] = $this->QR[$i][$j];
+                } elseif ($i == $j) {
+                    $R[$i][$j] = $this->Rdiag[$i];
+                } else {
+                    $R[$i][$j] = 0.0;
+                }
+            }
         }
         
         $matrix = new Matrix();
@@ -126,24 +126,24 @@ class QRDecomposition
         $Q = [[]];
 
         for ($k = $this->n-1; $k >= 0; --$k) {
-			for ($i = 0; $i < $this->m; ++$i) {
-				$Q[$i][$k] = 0.0;
+            for ($i = 0; $i < $this->m; ++$i) {
+                $Q[$i][$k] = 0.0;
             }
             
-			$Q[$k][$k] = 1.0;
-			for ($j = $k; $j < $this->n; ++$j) {
-				if ($this->QR[$k][$k] != 0) {
-					$s = 0.0;
-					for ($i = $k; $i < $this->m; ++$i) {
-						$s += $this->QR[$i][$k] * $Q[$i][$j];
-					}
-					$s = -$s/$this->QR[$k][$k];
-					for ($i = $k; $i < $this->m; ++$i) {
-						$Q[$i][$j] += $s * $this->QR[$i][$k];
-					}
-				}
-			}
-		}
+            $Q[$k][$k] = 1.0;
+            for ($j = $k; $j < $this->n; ++$j) {
+                if ($this->QR[$k][$k] != 0) {
+                    $s = 0.0;
+                    for ($i = $k; $i < $this->m; ++$i) {
+                        $s += $this->QR[$i][$k] * $Q[$i][$j];
+                    }
+                    $s = -$s/$this->QR[$k][$k];
+                    for ($i = $k; $i < $this->m; ++$i) {
+                        $Q[$i][$j] += $s * $this->QR[$i][$k];
+                    }
+                }
+            }
+        }
         
         $matrix = new Matrix();
         $matrix->setArray($Q);
diff --git a/Math/Optimization/GeneticAlgorithmInterface.php b/Math/Optimization/GeneticAlgorithmInterface.php
index da552a73e..904120aed 100644
--- a/Math/Optimization/GeneticAlgorithmInterface.php
+++ b/Math/Optimization/GeneticAlgorithmInterface.php
@@ -26,7 +26,7 @@ namespace phpOMS\Math\Optimization;
  */
 interface GeneticAlgorithmInterface
 {
-	public function mutate($a);
+    public function mutate($a);
 
-	public function unfitness($a, $b);
+    public function unfitness($a, $b);
 }
diff --git a/Message/Http/RequestMethod.php b/Message/Http/RequestMethod.php
index e7441f3bb..f7d5f6d61 100644
--- a/Message/Http/RequestMethod.php
+++ b/Message/Http/RequestMethod.php
@@ -28,10 +28,10 @@ use phpOMS\Stdlib\Base\Enum;
  */
 abstract class RequestMethod extends Enum
 {
-	/* public */ const GET    = 'GET';    /* GET */
-	/* public */ const POST   = 'POST';   /* POST */
-	/* public */ const PUT    = 'PUT';    /* PUT */
-	/* public */ const DELETE = 'DELETE'; /* DELETE */
-	/* public */ const HEAD   = 'HEAD';   /* HEAD */
-	/* public */ const TRACE  = 'TRACE';  /* TRACE */
+    /* public */ const GET    = 'GET';    /* GET */
+    /* public */ const POST   = 'POST';   /* POST */
+    /* public */ const PUT    = 'PUT';    /* PUT */
+    /* public */ const DELETE = 'DELETE'; /* DELETE */
+    /* public */ const HEAD   = 'HEAD';   /* HEAD */
+    /* public */ const TRACE  = 'TRACE';  /* TRACE */
 }
diff --git a/Stdlib/Graph/Tree.php b/Stdlib/Graph/Tree.php
index 2b271debc..7e8e8cb59 100644
--- a/Stdlib/Graph/Tree.php
+++ b/Stdlib/Graph/Tree.php
@@ -227,7 +227,7 @@ class Tree extends Graph
             $this->preOrder($neighbor, $callback);
         }
     }
-	
+    
     /**
      * Perform action on tree in post-order.
      *
@@ -240,7 +240,7 @@ class Tree extends Graph
         if (count($this->nodes) === 0) {
             return;
         }
-		
+        
         $neighbors = $this->getNeighbors($node);
 
         foreach ($neighbors as $neighbor) {
diff --git a/System/File/ContentPutMode.php b/System/File/ContentPutMode.php
index c7c88b1a1..89f12ffbc 100644
--- a/System/File/ContentPutMode.php
+++ b/System/File/ContentPutMode.php
@@ -30,8 +30,8 @@ use phpOMS\Stdlib\Base\Enum;
  */
 abstract class ContentPutMode extends Enum
 {
-	/* public */ const APPEND  = 1;
-	/* public */ const PREPEND = 2;
-	/* public */ const REPLACE = 4;
-	/* public */ const CREATE  = 8;
+    /* public */ const APPEND  = 1;
+    /* public */ const PREPEND = 2;
+    /* public */ const REPLACE = 4;
+    /* public */ const CREATE  = 8;
 }
\ No newline at end of file
diff --git a/Utils/Converter/Currency.php b/Utils/Converter/Currency.php
index 9fd65d0f3..4ff799f05 100644
--- a/Utils/Converter/Currency.php
+++ b/Utils/Converter/Currency.php
@@ -99,7 +99,7 @@ class Currency
     {
         if (!isset(self::$ecbCurrencies)) {
             $request = new Request(new Http('http://www.ecb.europa.eu/stats/eurofxref/eurofxref-daily.xml'));
-		    $request->setMethod(RequestMethod::GET);
+            $request->setMethod(RequestMethod::GET);
 
             $xml = new \SimpleXMLElement(Rest::request($request));
 
diff --git a/Utils/EDI/Edifact/INVOIC.php b/Utils/EDI/Edifact/INVOIC.php
index 07e1790c3..5100daae9 100644
--- a/Utils/EDI/Edifact/INVOIC.php
+++ b/Utils/EDI/Edifact/INVOIC.php
@@ -29,9 +29,9 @@ use phpOMS\Utils\EDI\Edifact\Components\BGM;
  */
 class INVOIC
 {
-	private $unh = null;
+    private $unh = null;
 
-	private $bgm = null;
+    private $bgm = null;
 
     public function __construct()
     {