public function retrieveMapData($left, $bottom, $right, $top)
	{
		// Set the API base
		$base = 'map?bbox=' . $left . ',' . $bottom . ',' . $right . ',' . $top;

		// Build the request path.
		$path = $this->getOption('api.url') . $base;

		// Send the request.
		$response = $this->oauth->oauthRequest($path, 'GET', array());

		return simplexml_load_string($response->body);
	}