function isValidCIFFormat($docNumber)
{
return $this->respectsDocPattern($docNumber, '/^[PQSNWR][0-9][0-9][0-9][0-9][0-9][0-9][0-9][A-Z0-9]/') || $this->respectsDocPattern($docNumber, '/^[ABCDEFGHJUV][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]/');
}