protected function compileLabel($aData)
    {
        if (!empty($aData['organisation'])) {
            return trim($aData['organisation']);
        } else {
            return implode(
                ' ',
                array_filter([
                    !empty($aData['first_name']) ? trim($aData['first_name']) : '',
                    !empty($aData['last_name']) ? trim($aData['last_name']) : '',
                ])
            );
        }
    }