diff --git a/test/CsvFileIterator.php b/test/CsvFileIterator.php
index 0783a43..ddc0b23 100644
--- a/test/CsvFileIterator.php
+++ b/test/CsvFileIterator.php
@@ -19,7 +19,7 @@ public function __destruct()
         fclose($this->file);
     }
 
-    public function rewind(): void
+    public function rewind()
     {
         rewind($this->file);
         //$this->current = fgetcsv($this->file, null, "\t");
@@ -32,22 +32,22 @@ public function rewind(): void
         $this->key = 0;
     }
 
-    public function valid(): bool
+    public function valid()
     {
         return !feof($this->file);
     }
 
-    public function key(): mixed
+    public function key()
     {
         return $this->key;
     }
 
-    public function current(): mixed
+    public function current()
     {
         return $this->current;
     }
 
-    public function next(): void
+    public function next()
     {
         $line = fgets($this->file);
         $current = explode(' ', $line);
diff --git a/test/CsvFileVerboseIterator.php b/test/CsvFileVerboseIterator.php
index 3ab02c5..25314b6 100644
--- a/test/CsvFileVerboseIterator.php
+++ b/test/CsvFileVerboseIterator.php
@@ -3,13 +3,13 @@
 
 class CsvFileVerboseIterator extends CsvFileIterator
 {
-    public function rewind(): void
+    public function rewind()
     {
         parent::rewind();
         $this->_updateKey($this->current());
     }
 
-    public function next(): void
+    public function next()
     {
         parent::next();
         if ($this->valid()) {