private function validateJuridical($vatNumber)
{
$checkval = 0;
for ($i = 2; $i <= 8; $i++) {
$checkval += $this->crossSum((int) $vatNumber[9 - $i] * ($this->isEven($i) ? 2 : 1));
}
$checkval = 10 - $checkval % 10;
return $this->checkCharacter[$checkval];
}