diff --git a/src/Calc/Calc.php b/src/Calc/Calc.php
index 417daec..523b6d8 100644
--- a/src/Calc/Calc.php
+++ b/src/Calc/Calc.php
@@ -85,7 +85,11 @@ class Calc
             if($collection->getName() == "opt") continue;
             if($collection->getFormel() != "") {
                 $formel = $this->formelCalc->parse($collection->getFormel());
-                eval('$var = ' . $formel . ';');
+                if(preg_match("/^[a-z](.*)/", $formel)) {
+                    eval('$var = "' . $formel . '";');
+                }else{
+                    eval('$var = ' . $formel . ';');
+                }
             }else{
                 if(!isset($this->engine->getVariables()[$collection->getName()])) {
                     $var = 'XXXXXXXXXXXX';
diff --git a/src/Calc/CalcValues.php b/src/Calc/CalcValues.php
index 9dc95b9..1febd14 100644
--- a/src/Calc/CalcValues.php
+++ b/src/Calc/CalcValues.php
@@ -90,7 +90,12 @@ class CalcValues
             if($collection->getName() == "opt") continue;
             if($collection->getFormel() != "") {
                 $formel = $this->formelCalc->parse($collection->getFormel());
-                eval('$var = ' . $formel . ';');
+                if(preg_match("/^[a-z](.*)/", $formel)) {
+                    eval('$var = "' . $formel . '";');
+                }else{
+                    eval('$var = ' . $formel . ';');
+                }
+
             }else{
                 if(!isset($this->engine->getVariables()[$collection->getName()])) {
                     $var = 'XXXXXXXX';
@@ -126,4 +131,4 @@ class CalcValues
         return $price;
     }
 
-}
\ No newline at end of file
+}
diff --git a/src/Option/Type/Template.php b/src/Option/Type/Template.php
index 6f5b819..01471c8 100644
--- a/src/Option/Type/Template.php
+++ b/src/Option/Type/Template.php
@@ -12,7 +12,7 @@ class Template extends Base
     /**
      * @return String
      */
-    public function getSelect(): String
+    public function getSelect()
     {
         return $this->select;
     }
@@ -20,7 +20,7 @@ class Template extends Base
     /**
      * @param String $select
      */
-    public function setSelect(String $select): void
+    public function setSelect($select)
     {
         $this->select = $select;
     }
diff --git a/tests/Customer/A/formels.txt b/tests/Customer/A/formels.txt
index 42fb7de..b71179f 100644
--- a/tests/Customer/A/formels.txt
+++ b/tests/Customer/A/formels.txt
@@ -693,10 +693,10 @@ if(!function_exists('getSammelformMengenAbschlagPlano')) {
     function getMaschine($breite, $hoehe) {
         if($breite > 49 || $hoehe > 49) {
 
-            return '"kba"';
+            return 'kba';
         }
 
-        return '"gto"';
+        return 'gto';
     }
 
     function getGeiferRand($format) {
@@ -730,4 +730,4 @@ if(!function_exists('getSammelformMengenAbschlagPlano')) {
     }
 
 
-}
\ No newline at end of file
+}