protected function getBooleanSelectList($includeNull = false)
    {
        $results = array();
        if( $includeNull ) {
            $results[ '' ] = Translate::recursive('common.both');
        }

        $results[ 0 ] = Translate::recursive('common.no');
        $results[ 1 ] = Translate::recursive('common.yes');

        return $results;
    }