code: public function BookingQuestions( $programme_start_id, $show_external = null ) {
  		$params = array();
  		if ( isset( $show_external ) ) {
  			$params['showExternal'] = $show_external ? 'true' : 'false';
  		}
  
  		return parent::GET(
  			"/$programme_start_id/BookingQuestions",
  			$params,
  			get_called_class() . '|' . __FUNCTION__
  		);
  	}
docs: @param integer   $programme_start_id
  @param bool|null $show_external
  
  @return mixed