code: public function dn( $domain, $singular, $plural, $number )
  	{
  		$singular = (string) $singular;
  		$plural = (string) $plural;
  		$number = (int) $number;
  
  		try
  		{
  			$locale = $this->getLocale();
  
  			foreach( $this->getTranslations( $domain ) as $object )
  			{
  				if( ( $string = $object->translatePlural( $singular, $plural, $number, $domain, $locale ) ) != $singular ) {
  					return $string;
  				}
  			}
  		}
  		catch( \Exception $e ) { ; } // Discard errors, return original string instead
  
  		if( $this->getPluralIndex( $number, $this->getLocale() ) > 0 ) {
  			return (string) $plural;
  		}
  
  		return (string) $singular;
  	}
docs: Returns the translated singular or plural form of the string depending on the given number.
  
  @param string $domain Translation domain
  @param string $singular String in singular form
  @param string $plural String in plural form
  @param integer $number Quantity to choose the correct plural form for languages with plural forms
  @return string Returns the translated singular or plural form of the string depending on the given number
  @throws \Aimeos\MW\Translation\Exception Throws exception on initialization of the translation
  
  @link http://framework.zend.com/manual/en/zend.translate.plurals.html