public function getAssertionsByEmailAddress($emailAddresses)
	{
		if (!$this->credentialsSet())
		{
			throw new Exception('You need to set the credentials first.');
		}

		if (!is_array($emailAddresses))
		{
			$emailAddresses = array($emailAddresses);
		}

		$query_params = implode('%20', $emailAddresses);
		$url = self::PASSPORT_API_ENDPOINT . "assertions?emailAddresses=" . $query_params;

		if ($this->request_type == 'oauth' && is_a($this->request, 'oauth'))
		{
			$this->request->setAuthType(OAUTH_AUTH_TYPE_URI);
			try
			{
				$this->request->fetch($url, null, OAUTH_HTTP_METHOD_GET, array('Content-Type' => 'application/json'));
			}
			catch (Exception $e)
			{
				throw new Exception('Assertations by email request failed.');
			}

			$response = json_decode($this->request->getLastResponse());
		}
		else if ($this->request_type == 'curl' && get_resource_type($this->request) == 'curl')
		{
			curl_setopt($this->request, CURLOPT_POST, false);
			curl_setopt($this->request, CURLOPT_URL, $url);
			curl_setopt($this->request, CURLOPT_RETURNTRANSFER, true);

			$response = curl_exec($this->request);
			$response = json_decode($response);
		}
		else
		{
			throw new Exception('Unsupported request type');
		}

		return $response;
	}